Massive algae bloom

[djbilo]

Bought this 1985 house with IG Gunite pool in May of this year.

Initial pool inspection showed some algae and my observation confirmed that so I got busy and brought the chemistry into line. .

Shocked and kept floating chlorinator stocked with 3" tablets and had good clarity and water chemistry.

Initial water test at LPS back in late May indicated calcium a bit high and the suggestion was just to add fresh water regularly to top off the level and that nothing else seemed amiss. I do not have a copy of that original report - it was hand-written and later reports are computer-printed.

Did this (topped off water) and until a few days ago all was well.

Suddenly noticed cloudiness in the water, on 9/5/13. Had water retested (results below) and added recommended clarifier. This time calcium was noted to be way high so it was also recommended to replace some water to lower it but before I could, disaster struck.

2 days later, algae bloom in full progress. Re-shocked. No effect. Had been told on 9/5 that with calcium level high, nothing else mattered/would be ineffective until it was lowered by dilution.

Repaired stuck pump drain valve (no backflush plumbed; it's a filter cart) and set to drain. Big flood in yard. Traced other end of the PVC pipe to the front corner of the house, an open-ended PVC pipe buried into the ground going into nothing next to the front corner of the foundation, so water exchange was tedious and first time limited to about 10", but did manage to do that much and also recycle the water since it is illegal in this city (Carrollton, TX) to dump pool water in the street or storm sewer.

Had another water test and just have watched it get greener and greener.

Now on 9/9/13 the pool is completely cloudy and totally green.

Here are test results both times:

9/5/13:

FAC, 5
TAC, 5
Calcium hardness, 630
Cyanuric Acid, 100+ (100 is highest they can tell)
Total Alkalinity, 120
pH, 7.2
Total Dissolved Solids, 950
Phosphates, 300

By 9/8/13 the results that we re-tested, to see if the partial water exchange impacted anything, look like this:

FAC 5+
TAC 5+
Calcium hardness, 340 to 390 (two tests in a row from same sample).
Cyanuric Acid, 100+
Phosphates, 500 (note how much they went UP).

There's nothing like waste or fertilizer nearby - and no one has been swimming in days due to the bloom.

My plan is as follows, and I wonder if some here could comment, including any effect on a few days' delay. Scheduling all this work will consume time on days I don't have this week due to a family wedding Friday/Saturday, so I am going to have to scramble to work something out as draining and refilling and then adding proper chemicals after to keep it from coming back will take time. Sunday seems the best day to attack it...it's so far gone at this point, I'm not sure a few more days will hurt THAT much, will it? Again, comment as you see fit and tell me if that's a really bad idea to wait just a bit until the hours are actually available. Right now I would not be able to hire a pro and anyway they wouldn't solve the drain plumbing issue (see below) - I have to do that.

1. Acquire backwash hose ($20 at Home Depot, 50', 1-1/2") and hose clamp to connect in-ground drain PVC to sanitary sewer cleanout opening (about 15' away). Per the City web site, this is acceptable - even just opening the cap and sticking the hose in - to dump water though is temporary. At some point I'll dig a trench and put in the required P-Trap and plumb it permanently but right now there's no time for that.

Turns out the Jandy valve and the way the drain is plumbed, you have to unscrew the Jandy valve handle to get it to clear the stop positions, but when you do that you can then rotate it into the 4th position (180 degrees from the "both inlets open" position - two inlets joined, open at the 9 o'clock position, all inlets open at the 6 o'clock position, and the Jandy-type threaded inlet (not used except for a water feature sometimes - the Baracuda uses main suction) open at 3 o'clock. This last position, which closes both inlet positions, is at the 12 o'clock position and I only discovered this one today after looking at the valve again and realizing I could maybe unscrew the handle and get it to rotate all the way around to block all inlets - the drain valve is T'd off before the Jandy valve.
2. Dump (per LPS and others who recommend similar, but not draining the entire pool) 1/3 to 1/2 of the water and refill on my watering day (voluntary 2x per week after 6 PM restrictions at present). To do this, set the Jandy valve to 12 o'clock and also remove the filter cart (no point filtering the water being dumped) and reassemble the filter housing with it temporarily out. Opening the drain valve with the PVC connected to the sewer, this will dump through the 1-1/2" PVC/Backwash hose at pump volume and based on quick test when I turned the Jandy, seems there is plenty of pressure/volume to drain fairly quickly.
3. Refill the pool and shock it - but HOW MUCH and HOW OFTEN? I need some advice on this part, much less if draining up to 1/2 the water is enough given this is a full-fledged cloudy green mess (I do have a photo of it but can't post it right now).

What about the chlorine tabs? They have CYA and if that level went high and caused all this after only a few months, presuming that original test was checked for it but the level wasn't abnormal back in May - I have no way to know for sure - I obviously want to avoid a repeat. Had thought I might get through this season without a water exchange of this magnitude but not any more.

LPS suggests at least 1/3 of water be exchanged in this climate at the start of each season. Valid recommendation? Based on all the online material, LPS staff comments and suggestions, and the fact that the last time I had a pool was 13 years ago when we owned another house a few miles south, I am a little rusty. Plus, nobody seems to answer the same question the same way so it is hard to know what's valid and correct, versus misinformation or worse, misleading information (intentional or not).

Do plan to order a better test kit than I have (though so far I'm unimpressed with a $68 cost and $17 to ship such a small package, the TF-100 recommended here), to avoid repeated trips to the LPS but they know I have a problem and have been very helpful to run any tests I request even though they really only offer the freebie once a month per address (Leslie's).

It was a surprise, somewhat, to see the phosphate level increase after the limited water exchange, too. Not sure what to make of that and of course that is part of the algae's feeding frenzy.

I've tried to give accurate information about the pool's sizing based on info I have in the previous owner's statements and inspection report though nothing exactly specifies it. I need to do a more detailed calculation at some point, of course and will but for now I'm more interested in making wider swaths here to kill the problem completely and then start anew. Once in our other house I did a total water replacement, and this time I was hoping to avoid it but some material I read said that with CYA as high as this could be (including the 50/50 dilution of pool water with tap, to test and see about how high it really was - haven't done that yet), it might be hard to dilute the CYA enough without dumping the whole thing.

Also, and finally, it seems this whole thing went massively wrong so quickly I didn't really even have time to react over the weekend, due to the fact I had drain repairs to make and to figure out some legal way to dump water in the first place; took time researching the city web site on the weekend to find the answer but I finally did.

The initial dump took about 7 hours and only dropped it about 10", and this with constant attention and tweaking. Refilling it this time, I've essentially wasted that fresh water but there's nothing I can do about it.

Now that I have figured out the Jandy valve position which isn't "accessible" normally, I should be able to speed things up and probably can avoid a sump pump this time around, which would mean I'd have to string a longer hose from the pool to the front yard where the sewer cleanout is located anyway, than I have to with the in-ground PVC drain pipe and a clamped-on backwash hose to reach it. I had planned to buy a 50' backwash hose, trim about 15' feet for this use, and save the rest for other applications if the 15' piece were to fail later. If I don't cut it, it would work for the sump pump if I have to go that route, but the 50' length for the drain PVC to sewer isn't going to work - too much excess length to manage in that 15' distance and it would just be wrapped in circles.

In closing, I found this article online that discusses the CYA 'problem'. Anyone have any thoughts about it? It seems enough well-reasoned though it's dated 1997. The CYA level seems to have precipitated all this so I will have to watch closely...or was it first the elevated calcium followed by that? Hard to tell.

http://www.ppoa.org/pdfs/PrP_Cyanurics% ... 20Bomb.pdf

Thank you in advance.

 

[kimkats]

There is really no way YOU can control your pool with out a GOOD test kit. In the long run it will save you SO much money and time!

There is story after story on here about how wrong the pool store tests are.

Your high CYA is the major cause of your problems.

Good luck!

Kim

 

[Patrick_B]

Welcome djbilo,

There is a lot to respond to here and I'm going to take just a few bites to give you some essentials.

The situation you have is pretty common. Pool Stores do not educate their customers and they wind up exactly where you are.
Over stabilized, under Chlorinated and with a giant mess.

To change it you have to be in control of the pool yourself, test your own water, trust the results, and treat the pool yourself with a clear understanding of what you are putting in and why. You can say that so far you are unimpressed with a $68 dollar kit and $17 express fee, but how much have you spent with LPS to get you here? If you get it and learn to use it, see the results it gets you, you'll think you should have paid double for it. I am even less impressed with the hundreds of victims I've seen come here in my two years with your exact situation. I have a neighbor I'm helping right now that's a carbon copy of your situation as well. Just started with her this weekend. We see this very unimpressive situation every day here in pool season.

Part and parcel of all this is education. You have to be willing to learn some fundamentals of Pool Chemistry. Everything you need to know to have success is right here, and it's easy. Spend a little time reading and asking questions, and you'll learn all you need to know. I understand and sympathize with you being frustrated, I would be too, but this is really easy once you learn some basic stuff. Order the kit, lets see where you really are and start reading in Pool School. Start with the ABC's of Pool Chemistry, and then everything else in there as you can absorb it. As for the "shocking" times and methods, all that info is in the SLAM process. You'll have to complete one and we can help you learn how to do it. It's easy too. As for the Phosphates, they mean nothing in a properly chlorinated pool. Nothing at all, so don't worry with them, period.

Post back, and we'll help you learn to fix this and stay out of it from now on.

 

[Bama Rambler]

Welcome to TFP.

Let me see if I can wade through this.

As Kim said, the first thing you need is a good test kit. Order the TF-100 and a Speedstir from http://www.tftestkits.net or http://www.poolsupplyworld.com if you're on the west coast.

1. You'll no doubt need the waste hose so that's a good plan.

2. I suspect you may have to do that more than once to get the CYA down. Since we don't know how high your CYA really is starting with a half drain is a good start. Once you get a good test kit there are ways of testing it over 100 even though you lose some accuracy.

3. How much your FC needs to be all depends on what your final CYA is, and how often is about once per hour in the beginning. We recommend only using bleach. It adds FC quickly and doesn't add anything you don't want.

Chlorine tabs add CYA chlorine powder either adds CYA or CH. Both of which are already too high.

If you follow the recommendations here you never have to replace water due to high CYA because we have the knowledge and use products that prevent it from getting too high. There are areas where the fill water is high in CH and in those areas some draining and refilling may be needed but with proper management, you can go a long time between drains.

You say you're unimpressed with the cost of the test kit. Are you impressed with the algae you have or the amount of chems you've had to buy. In your situation the kit (and shipping) will pay for itself almost immediately.

Don't worry about phosphates at all. They are irrelavent.

 

[Charlie_R]

Welcome to TFP! You have landed in the right place to learn how to control you pool, get it algae free, and keep it that way.

Strong suggestion -- Dump the pool store, and take control of your pool. There is a reason that you read so much on here and at other BBB advocating forum about buying an FAS-DPD based test kit (by the way, it is an investment not an expense!).

Next suggestion -- read Pool School, linked in the upper right of this page, particularly the sections on:

pool-school/pool_water_chemistry

pool-school/chlorine_cya_chart_shock

pool-school/recommended_levels

category.php?c=pool_chemistry

Then when you have read through those a couple of times, read these:

pool-school/defeating_algae

pool-school/shocking_your_pool

Yes you can wait a couple of days before taking care of this.

The only thing the pool store has right in your description is the drain and refill.

Your CYA got that high because of the use of tab/pucks. ALL of those contain CYA. Search here for how much each type of tab/puck adds. This is why we consistently advocate the use of liquid chlorine, a.k.a. household bleach. Bleach does only two things and does them very well, and those are sanitize your pool and keep it algae free. It doesn't change any other chemical level while doing it.

Phosphate levels do not matter. Analogy: A house with cupboards full of food, with no one there to eat it. If, by keeping your pool chemistry at proper recommended levels, you have no algae to eat the phosphates, does it matter if they are there or not?

You have not wasted the fresh water, as long as you haven't added more CYA to the mix. You will need to get that down to a more reasonable level. We recommend 30-50. You will need to drain and refill several times to achieve this. Otherwise you will be needing bleach by the drum to clear your pool.

Could you do us a favor and read this section of pool school, and add your information to your profile/signature?

pool-school/read_before_you_post

It would help us to help you more efficiently.

The article you refer to has been discussed here many times. Search for posts by chem geek. He has a wealth of info concerning pool chemistry and the how and why of it, including detailed info on CYA and it's uses.

Edit: I see there are several experts chiming in here, and I would expect them to add details to what I've posted here.

 

[ship of fools]

The test kit is the best thing that ever happened to my pool ..... i was hesitant to buy it at first as well

You can read post after post after post on here about situations just like yours that are now resolved and trouble free ..... or you can continue to trust the pool store

 

[Bama Rambler]

Once you do a little reading around here you'll find that we understand the FC/CYA relationship quite well. CYA buildup is a huge problem because two of the most common forms of chlorine for pool sanitation contain a lot of it and it doesn't go away without draining.

While the CH can be a problem it can be managed at fairly high levels with the proper balance.

Follow the advice you get here and read Pool School and once you're past this episode, you will soon see just how easy it can be to manage a pool and not have to expend great amounts of time or money.

I have never "shocked" my pool even once. I chlorinate with bleach and it stays crystal clear. Yes, I have a severe case of sparklypoolitis and I hope that you have it soon as well.

 

[djbilo]

There is so much to say to all the great informational replies, and all in a single 24-hour period!

First let me start by saying thank you. THANK YOU! Thank you to everyone who has posted. I already feel better. My wife is a bit skeptical at this point; admittedly, you get to this point and you do have to throw a bit of money at the problem.

Next, one post wants information in my signature. That information is there - as much as I have at the present time, so if something else key is missing, please let me know. I re-checked. All the info I have is present in the sig.

I do not know when the pool was built. I may be able to search the county records and find out when the permit was issued, and whether it listed the # of gallons. I've spent the evening trying to estimate. I am in the ballpark of 15,000 to 18,000 and I don't like that margin of error so I will have to work on that number and iterate to a more precise one.

As for the 'unimpressed' comment, turns out the TF-100 ordering site has a glitch and my report of it to them will result in a fix. Shipping likely is about half that or less, and they didn't realize the site had an update that was needed.

Meanwhile, I have done the following today/this evening.

First, I read all the basic Pool School articles last night. It went fairly quickly and I'll be re-reading them multiple times, but it all was very informative.

Next, I was able to get a 50' vinyl hose, some PVC pipe and fittings, and I fashioned a drain coupler from the end of the pool drain in the ground to the sanitary sewer nearby...and to test it I basically watered the heck out of my dry yard (Dallas area, low water/drought). Now, my pool drain is above-ground and has a threaded cap, plus the hose has a threaded fitting and is clamped on the PVC pipe to screw in when I need it. I also can get a faucet adapter (later! Too much money spent this period) and have a place to hook a garden hose to recycle water I need to drain.

I then dumped 18" of pool water using the pool pump. It didn't struggle at all and held a very good flow - I did remove the filter cart (cleaned it), and did use the vacuum hose in the skimmer to suction the water by weighting the hose with the vacuum head. That leads me to a question I've NEVER understood about these plumbing designs. I'm sure I can google it and find out, but I get someone here knows the answer off the top of your head.

In the skimmer there are 2 outlets/holes - one (outside hole from the perspective of the pool) is the main pump draft/suction where the vacuum hose goes. What's the other? Is that the bottom-of-the-pool drain that comes up through there? I've always wondered and never have known. If so, is there a way to connect that hole to the suction hole (standard size, some kind of tubing/fitting) to let it draft the water from the very bottom to avoid the whole sump pump routine? If suction and air seal are maintained, the pool pump doesn't care - so long as there's not a lot/very little air, it will just pump away as those things are designed for continuous duty SO LONG as they have water. Sorry, it's kind of a dumb-sounding question but the drain pipe - where DOES it go, and if not to that 2nd hole, what's that hole for? One never really notices any 'outflow' from that inner hole, as if it is suctioning from the drain on the bottom/deep end.

So, when the vacuum hose started to "squeal" (aka leak air excessively) as the level got lower I removed it and of course lost the prime instantly. Rather than struggle to get it back I shut off the pump, rented a submersible pump and with the included hoses am dumping more water now.

I'm having to eyeball about what's half. I think I noted that the pool's circumference is about 90' - slightly less, that's the distance around the desk seal at the outer edge of the coping. The deep end in the center does slope to about 8' and the shallow end is about 3.5, out 5-6 feet and then sloping to the deep end. Currently 30" of water has been removed. Given that the volume removed is level, a close approximation of the volume removed seems to be about 875 cubic feet, which is about 6550 gallons so far. If this is an 18,000 gallon pool I am at about 1/3 and based on my estimates I'm shooting for half, so another hour of pumping with this pump and I should be there.

HERE IS MY MAIN QUESTION: When I bought the plumbing, I did get some algaecide and non-stabilized powder chlorine. They did have liquid chlorine for about $5/gallon. It has about 11% available chlorine and the powder has nearly 50%.

Household bleach seems to have between 3 and 10% available chlorine - would a standard store-brand bleach be ok for this application? Honestly I never in my LIFE thought about using household bleach. Talk about education! There you go. I'm sure the answer is here somewhere but how many gallons of plain household bleach per 10,000 gallons of water?

To get me by, I did also buy some 6-way (no phosphate check) test strips with the color chart on back. I figure that to be a quick way to get some kind of indication of the situation and a general trend while I wait for the TF-100, and it did align with the tests in the pool supply place - the starting measurements were very similar by my color comparison to the #s I got the other day.

MY OTHER MAIN QUESTION: If I only dump 1/2 of this terribly green water, then I really need to aggressively treat the remaining green water to kill everything - BEFORE refilling? After? During (algaecide, wait 24 hours, shock, while filling?) I'm unclear, and it does seem counter-intuitive to dump only half of the algae-fied water and try and treat the rest but I am going to resist the temptation to just pump it all out and stop tonight when I get to about half and let more guidance send me in a direction.

SO, I need further guidance here and will continue reading too. Happy to do both to get to the best, quickest answer so I can keep the overall risk low.

Tomorrow I'm able to work from home so will check the board during the day and see what input I get and adjust my plans accordingly as I take a break for a few minutes. I can return any of the unopened powder non-stabilized chlorine if just some plain household liquid bleach would be better - how much (# gallons per 10,000 pool gallons or something)? Any favorite brand or store/brand?

Again, I want to THANK you all for your information, your encouragement, and your patience. I do not plan to be a 'greenie' for much longer and I know I will get through this with some learned help.

 

[djbilo]

Do I want the TF-100 or the K-2006?

Looks like I will be returning some dry chlorine and algaecide and going to WalMart for store brand bleach. My wife is going to think I've turned into a loon. "Dear, let's go to WalMart. I need 8 million gallons of store-brand bleach"

 

[cadman89113]

TF-100 will give you MORE bang for your buck ($) for what we are doing here.

 

[djbilo]

With the test strips, half the water drained, the numbers are:

CH 400
Fc/bromine 10/20
pH 7.5
Alk. 80
cya 150

Lacking other info added walmart chlorine to start killing the algae, rinsed and brushed the sides, hand mixed the water a bit and 4 hours later tested these numbers:

CH 400
Fc/bromine 10/20
ph 8.4 (!!!!)
Alk 180-240 (hard to tell for sure)
CYA 150

Should I proceed with a refill in the morning? I will re-test before and also note visual changes from overnight sitting with 6 gals walmart bleach....at least I could see an immediate imoact, unlike powder shock from before all this.

This stuff has sodium hypochlorite. Any issue with the sodium?

Now I begin to see why salt or gas chlorinators are so beloved by their owners.

 

[Shane1]

There is so much to say to all the great informational replies, and all in a single 24-hour period!

HERE IS MY MAIN QUESTION: When I bought the plumbing, I did get some algaecide and non-stabilized powder chlorine. They did have liquid chlorine for about $5/gallon. It has about 11% available chlorine and the powder has nearly 50%.

Household bleach seems to have between 3 and 10% available chlorine - would a standard store-brand bleach be ok for this application? Honestly I never in my LIFE thought about using household bleach. Talk about education! There you go. I'm sure the answer is here somewhere but how many gallons of plain household bleach per 10,000 gallons of water?



MY OTHER MAIN QUESTION: If I only dump 1/2 of this terribly green water, then I really need to aggressively treat the remaining green water to kill everything - BEFORE refilling? After? During (algaecide, wait 24 hours, shock, while filling?) I'm unclear, and it does seem counter-intuitive to dump only half of the algae-fied water and try and treat the rest but I am going to resist the temptation to just pump it all out and stop tonight when I get to about half and let more guidance send me in a direction.

SO, I need further guidance here and will continue reading too. Happy to do both to get to the best, quickest answer so I can keep the overall risk low.

Tomorrow I'm able to work from home so will check the board during the day and see what input I get and adjust my plans accordingly as I take a break for a few minutes. I can return any of the unopened powder non-stabilized chlorine if just some plain household liquid bleach would be better - how much (# gallons per 10,000 pool gallons or something)? Any favorite brand or store/brand?

Again, I want to THANK you all for your information, your encouragement, and your patience. I do not plan to be a 'greenie' for much longer and I know I will get through this with some learned help.

This site really is one of the best out there.

Return all the other chlorine products and just use store bought plain unscented bleach. I use Target brand bleach but you can get it from anywhere you like. Target has the best prices in our neck of the woods. As far as how much to get....get enough in your cart so that people look at you weird and think what is this person up to.

Dont SLAM the pool until after the partial drain is complete and you have all of the gunk out of the pool. I didnt have time to read everything so I'm not sure if you have vac'd to waste to remove all of the large organics that might be at the bottom of the pool. Your water will still be over stabilized until you start to refill. At that time the CYA will mix in with the new water and dilute to managable levels. Good luck and welcome to the site!

 

[Charlie_R]

Since your CYA is still reporting 150+ with strips, you will need to dilute that with fresh (CYA free) water. This means you refill before treating. That is the whole point in "drain and refill", to lower your CYA.

If you have leaves and other trash in the bottom of your pool, by all means available to you get as much out as you can while you are refilling. I realize you can't see the bottom of the pool. Just keep scooping with your net, and brushing towards the middle, then scoop again.

Once you are refilled, then test again. If your CYA still tests above 50, repeat the drain and refill. I wouldn't start adding chlorine until your CYA is at an easier to manage level, but do keep stocking up on it. You will need it. There is no way to give an estimate of how much chlorine you will need.

For your skimmer, there may be a tool that will connect the two tubes that come into it. Hopefully, it was plumbed as you suspect, with the main drain connected to the second tube in the skimmer. That is normally the way it is done. However, from your description, it may have been plumbed backwards. By this I mean that the pipe to your pump should have been into the more central of the two with the main drain connected to the hole on the side.

Your wife will be a lot less skeptical once she starts seeing the pool get less and less green once you start pouring the bleach to it. She will thank you for finding this site when she sees a crystal clear sparkly pool again.

With the knowledge gained from this forum, you will be able to keep your pool in beautiful condition with a lot less work and $$ out of pocket.

Do invest in the TF-100, with the XL option. Consider also the SpeedStir. No one that has done either or both of the options has ever regretted the decision.

 

[Bama Rambler]

I do not know when the pool was built. I may be able to search the county records and find out when the permit was issued, and whether it listed the # of gallons. I've spent the evening trying to estimate. I am in the ballpark of 15,000 to 18,000 and I don't like that margin of error so I will have to work on that number and iterate to a more precise one.

Don't worry about it too much. Start with about 16,000 and use the pool calc to calculate the chems and then depending on whether you over or under shoot the target you can adjust the size over time.

In the skimmer there are 2 outlets/holes - one (outside hole from the perspective of the pool) is the main pump draft/suction where the vacuum hose goes. What's the other? Is that the bottom-of-the-pool drain that comes up through there? I've always wondered and never have known. If so, is there a way to connect that hole to the suction hole (standard size, some kind of tubing/fitting) to let it draft the water from the very bottom to avoid the whole sump pump routine?

In some systems the second port in the bottom of the skimmer is indeed hooked to the main drain. There's a diverter that goes in the bottom of the skimmer that diverts the water from the skimmer to the main drain when the level in the skimmer gets too low. It either looks like a space ship or a twinkie. Tell us whatever you can about the skimmer and maybe we can figure out which it is.

HERE IS MY MAIN QUESTION: When I bought the plumbing, I did get some algaecide and non-stabilized powder chlorine. They did have liquid chlorine for about $5/gallon. It has about 11% available chlorine and the powder has nearly 50%.

Household bleach seems to have between 3 and 10% available chlorine - would a standard store-brand bleach be ok for this application? Honestly I never in my LIFE thought about using household bleach. Talk about education! There you go. I'm sure the answer is here somewhere but how many gallons of plain household bleach per 10,000 gallons of water?

Return the algaecide. Unstbilized chlorine is most likely Cal-Hypo. It adds calcium to the water. If your CH is as high as the strips indicate, you don't want to keep adding it. Take it back too.

I use Dollar General bleach almost exclusively in my pool. It works great and is the least expensive option where I am.

Now to finally answer the question. The only way to know how much bleach you need to add is to measure accurately and then use the pool calc to figure how much to add.

MY OTHER MAIN QUESTION: If I only dump 1/2 of this terribly green water, then I really need to aggressively treat the remaining green water to kill everything - BEFORE refilling? After? During (algaecide, wait 24 hours, shock, while filling?) I'm unclear, and it does seem counter-intuitive to dump only half of the algae-fied water and try and treat the rest but I am going to resist the temptation to just pump it all out and stop tonight when I get to about half and let more guidance send me in a direction.

The reason for dumping the water is to get the CYA to a manageable level. Once you have done that, you will start the SLAM process to clear the pool. However, if you don't have to worry about the water table in your area and you can refill the pool all at one go, you can empty the pool and scrub it with a mild bleach solution and start over. That is certainly an option. In most places where there aren't water restrictions, the cost of water to replace the entire pool and the cost of bleach to clean it up is pretty close to the same.

If you decide on a full drain/refill let us know and we can guide you through that as well.

 

[djbilo]

I just took the rented pump and hoses back to save a few bucks (penny wise, pound foolish I suppose) - most folks had advised against dumping all the water in lieu of 1/3 to 1/2.

I got the Wal-Mart store brand bleach, and I did pick up some liquid chlorine at Home Depot while returning the pump, to have enough on hand.

I should have tested before I went. My pH is high (8.4). However, if I start adding water it will come down of course.

This morning's #s (remember, using test strips for now as I don't have the kit yet)

TH 200-400 (color appears in between)
FC/Brom 10/20
pH 8.4
TA 120-180 (appears in between)
CYA 300 - with better (day)light and confidence of a color match, I wonder if my readings last night were off due to the lighting.

Since dumping the water doesn't change the concentration of CYA, filling it would dilute it but to what degree remains to be seen.

Starting completely over, which I originally intended but paused based on all the advice...well, I'll try not to second guess.

Since I returned the pump, if I refill at this point and initiate the SLAM process, which appears to require the pool to be full to circulate water, how confident should I be that doing it this way - diluting the still-present algae and then SLAMing it - will work? I'm curious about anyone's degree of confidence in success given the info I have provided.

I ask because it is cheaper to re-rent, or just go ahead and spend the $60 and buy, a pump and finish off the water replacement, though I'm throwing away money either way as I added chlorine overnight.

Bigger question: Bleaching the sides while the water level is low - how important overall? As well, should I just go ahead and dump the rest of the liquid chlorine I have on hand before filling? SLAM says I need a high level all at once.

What are the risks of waiting to refill, on the arrival of the good test kit (I have to order it TODAY) - filling will take the greater part of a day, and then the strips don't resolve higher chlorine levels but will at least give guidance, compared to doing nothing to the level right now, bleaching the sides (I seem to have plenty of bleach!), and waiting for the better kit.

Recommendations?

 

[djbilo]

TF-100 ordered. It will take a couple days to get here. Meanwhile I will limp along with test strips and advice anyone can provide for this interim period of waiting.

 

[Bama Rambler]

If you decide to refill and SLAM it, and you follow the process correctly, it will work.

Whether you decide on a complete or partial drain/refill, you can get sparkly water.

You will need to refill the pool before starting the SLAM process. You will also need the good test kit in order to perform the SLAM process correctly.

I suggest you decide on whether you want to refill from this point or do a complete drain/refill.

 

[djbilo]

Dave J, I guess the decision to finish the drain and start over, versus refilling at this point and SLAMing, rests on whether I do not properly solve the calcium/CYA levels with only a partial. If I do not finish the drain I can only bleach wash the part currently exposed. Wondering if that is good enough.

Am currently undecided but feel I have to decide today, kit or no kit. That is my point of uncertainty...refill now and fly without a parachute, or finish draining, refill and fly without the same (test kit) parachute.

Tough choice. I do not see an advantage one way over another so if someone does by all means, I am all 'ears'.

 

[Bama Rambler]

Here's my strictly personal opinion. You've already drained half and you shouldn't have a water table issue, so I figure it's a wash on the cost of the additional water and the bleach. In fact the bleach may cost more. In my case, 16,000 gallons of water would cost me about $50 so I would drain, wash and refill if it were me. By the time you get it washed and refilled you will have the test kit and can start out with a fresh fill the right way. It'll cost you a little bit to add the CYA back but not too much.

 

[DorsalSpine]

My $.02

I did two partial refills to get my CYA down to 60 which is at least manageable. I didn't have the option to do a complete drain since I have a vinyl lined pool. With everything I have learned this year I would have done a complete drain if it had been an option.

A good test kit is an absolute requirement. I can't begin to tell you how good it feels to understand what is going on and how to fix it.

If you can wash and refill while you wait on the test kit, I would do it. If your CYA ends up over 100 after a partial refill, which it sounds like it might, you are right back to square one. At least with a fresh start you know exactly what you have. With careful record keeping, you can manage a clean refill in the short term while you wait on the test kit. Having said that, don't wait to buy the kit. It is essential!

My wife thinks our pool has never looked better and I'm spending way less time and money on keeping that way since I found this site a couple of months ago. My only regret is the ten years I wasted previously following pool store advice.