New pool owner trying to convert to BBB

[himself]

Hi all!

Just moved into our new home and we have a pool! It's a 12k gallon in ground plaster pool with a water fall. 1HP pump (no idea what flowrate on the pump is) with a DE filter, automatic chlorinator (stupid trichlor :grrrr: ), mineral feeder (more on this later), and automatic pool cleaner with booster pump. When we first moved in, I went straight to the closest Leslie's and asked for advice. If only I would have searched a little more first!'

Basically it went like this: We moved in and I checked the pool right away with the test kit the previous owners left behind. This is what I got:

FC: 1ppm
PH: 7.2
TA: ?? (Couldn't figure out how to use it)

Being busy with moving, I didn't touch it again for 2 days. During this time the pumps continued to run on the automatic timer for about 4 hrs per day. On the fourth day, I tested it again. This time FC read 0 and pH was still 7.2. I was a bit alarmed at this, so I brought a sample up to the Leslie's. They confirmed I had no chlorine, and gave me the following results:

FC: 0
CC: 0
CH: 750
CYA: 100
TA: 90
pH: 7.5
TDS: 1300

The fellow at the Leslie's informed me that my pool needed to be shocked and that I should crank the chlorine feeder up to 4. So I bought a $40 box of dichlor packets and was on my merry way. By the time I got around to putting in the dichlor, we were getting a little bit of green stuff on the walls of the pool but the water was still clear. I put the dichlor in that evening and checked the chlorine in the morning. It was over 5 ppm so I couldn't really tell what it was. Another test from leslie's that evening and I'm back down to 4 ppm FC.

Fast forward a week of reading TFP and desperately trying to get rid of the green in the pool, and here I am now trying to convert this pool to the BBB methodology.

I've come to realize that the previous owner was a devoted follower of the Leslie's down the street. They went with trichlor pucks in an erosion feeder, a Nature2 mineral feeder, and dichlor packets for shocking. I believe the leslie's test results sort of prove that with the really high CYA and CH.

I've set a goal. I'd like to get the water chemistry close to:

FC: 4ppm
CH: 300
CYA: 50
TA: 100
pH: 7.5
borates: 50 ppm (maybe later)

In my attempts to do this, I've drained roughly 33% of the water by running the pump to waste and then refilling with city water. Our local water has high TA (I tested it) of 200. After the water change I was at:

CYA: 75
TA: 160
pH: 6.8
CH: 550

I've totally turned off the the auto feeder at this point and am only adding chlorine using 6% bleach. I've manged to get everything pretty much stabilized at an FC: 5ppm. I've been running the pump ~8 hrs / day and adding about 75oz of bleach every night. The actual amount varies a bit, but I just check it, check poolcalculator, and then add as directed. I'm aerating the pool using the water fountain in an attempt to raise the pH so I can get the TA down. My plan is to keep repeating the drain/fill/lower TA cycle until I reach my CH and CYA goals. Currently, the TA is sitting around 160 and a pH of 7.5. Once I get the TA down to 80 or so, I'll do another drain/refill.


So.... How am I doing? Is this about what I should be doing?

I've got a question about lowering the TA. From what I can read, it would seem that the recommend way to do this is to get the pH up to 7.8 and then lower to 7.2 with muratic acid. How do you know how much that is going to lower the TA? What happens if you lower the TA too much? Add baking soda to bring it back up? Doesn't the baking soda raise the pH then?

Lastly, the former owners have installed a Nature2(http://www.nature2.com/poolproducts/aboveground/nature2_express.asp) on the PVC return from the DE filter. I'd like to get rid of it. Any suggestions on how to do this? Should I just take out the cartridge and leave it be? I've ordered some metal test strips from diywatertesting.com to check and see how much has accumulated in the pool.

Thanks in advance for any help or advice!

 

[cardiacmommy]

You mentioned some green ... how is the water color currently? I'm a newb myself but it sounds like you have never gotten the pool to shock value..which with cya 75 would be 21. From a fc of 5 that would be 415 oz bleach.

Do you now have a way to test your numbers from home? You mention the pool calculator so I'm not sure.

 

[JohnT]

Welcome to TFP.

Lowering TA just involves lowering the pH to around 7. That's all it takes to lower the TA.

But....you need to get your pH back up where it should be without raising the TA again. You do that by aerating the water, and your water fall will do a dandy job of that.

I wouldn't get too worried about TA until you get your CH under control. That's going to involve more water changes, and that will also get your CYA down where you want it. During the TA lowering process, you will probably want to run your pump more than the 4 hours to speed things along.

You can just pull the cartridge from your Nature 2.

 

[zea3]

You can remove the mineral cartridge and leave it be for now. Down the line if you decide you want to change the plumbing around you could remove it then. You do need to shock as soon as you are done draining/refilling. There is no point in getting the TA down and then draining/refilling again. You will waste money balancing water just to drain it again. Go ahead and finish the drain/refill, shock until you pass the overnight test, and balance the water. According to the Pool Calculator with your current CYA level your daily FC target is 6-11 ppm. 5 is just below your target range and you are likely on the verge of a full algae bloom. Your shock level is 21 ppm. You would need to raise your FC to 21 and keep it there until you pass the overnight test. For the overnight test you test the chlorine at night after the sun is off the pool and test again in the morning before the sun comes up. There should be a FC loss of 1 or less to pass the test.

 

[frustratedpoolmom]

I agree with Zea - finish the drain/refill process and get the CYA/CH down.
Then get the PH to 7.2, and begin to shock using the CYA level as reference to determine your shock level.
Complete the shock process, and then work on your TA.
The Effects of Adding Chemicals section of the Pool Calculator tells you how much the TA will be lowered by the acid addition - check it out and give it a try.
Do you have your own kit yet?
You are doing great

 

[himself]

Thanks for all the advice!

The pool is a nice blue/clear color now. Sparkly too! :-D

I'll pull that cartridge out of the nature2 today. Also, I'll go ahead and finish the drain/refill to get the CYA and CH under control, and then deal with everything else.

I do have my own test kit now. It's a decent taylor kit (rebranded to leslie's) that lets me do FC, TC, pH, and TA.

I've also got a TF100 on the way so that I can test FC above 5, CH, and CYA.

I've also ordered some metal test strips from Lambert's so I can check the metals. From what I've been reading on the forum about the nature2, people normally make it about 3-4 years before they start to get problems. The pool is now 2 years old and I figure that thing has been on there since the pool was built.

 

[frustratedpoolmom]

The drain and refill will help with any metal level issue.

 

[himself]

A little more follow up...

Last night before going to bed (well after sunset), I check the FC and it was 3 PPM. I checked it again this morning first thing before sunup and it read the same 3ppm. Does this mean I can probably forgo shocking until I've finished with the draining and refilling?

I added about ~100floz of bleach before going to work, so I should back up around 7ppm. I normally add the bleach at night, but I wanted to see if I would loose any overnight so I waited till morning.

TF100 kit should be here today, so I'll finally be able to test CYA and CH on my own! No more dodgy pool store guy to deal with.

 

[frustratedpoolmom]

That's a good sign...you should forgo shocking anyway as Zea mentioned.

 

[himself]

I have my first set of results from the TF100 kit I got in today. This is what I came up with:

FC 9.5 ppm
pH 7.5
TA 160
CH 880!! (Took me two tries to get it to change to blue, so I may still not be doing it right.)
CYA 80

After I did the test above, I drained another 40% or so of the water and am in the process of refilling now. While the water was down, I took the opportunity to take a picture of the pool.

I noticed that there was something on the plaster above the water line, but I'm not sure what it is. It almost looks like they are just wet spots.

Anyway, it's been a rather exhausting evening. While waiting for the pool to pump down I was busy rewiring the phones to RJ45.

I'll post again tomorrow with some more details and test results of the drain/refill.


Edit:

I just went and checked the pool after refilling:

FC: 3.5
pH: 7.2
TA: 150
CH: 790
CYA: 70

Not quite the drop I was hoping for. I suppose more drain/refill's are in my future.

 

[frustratedpoolmom]

I spoke with one of our plaster experts and he told me based on the pics and your CH level the pic shows severe scaling....

He's out of town but I'm sure as soon as they can one of those "in the know" will post back...

 

[JasonLion]

From the look of the picture, you are getting some calcium scaling. Calcium scale will have a rough surface that sits on top of the plaster.

You should measure the TA and CH level of your fill water. It seems likely that the fill water CH level is rather high. If your fill water CH level is indeed high, this is going to be an ongoing problem that you will need to learn to live with. If your fill water CH level is low, then this will be a one time issue that can be avoided in the future.

When dealing with high CH levels, it is important to keep the PH and TA level consistently low, or you run a risk of calcium scaling. You can use the Pool Calculator to get a sense of your CSI (calcium saturation index). You want to be very careful to keep your CSI below 0.6 at all times. The other thing you can do is to add some sequestrant, pick a kind that is optimized for high CH levels. The ones you want are often labeled as good for fresh plaster.

Calcium scaling is very difficult to remove. The best approach for extensive scaling is to drain the pool and do a manual acid wash. Sometimes calcium scale can be removed by getting the CSI down to -1.0 and adding calcium optimized sequestrant, but doing this is tricky and usually doesn't work.

 

[himself]

Sorry for the delay in posting back. Been quite busy trying to finish the final bit of move out from our former home.

I've done two more drain and refills since I posted last. I finally got around to testing our city water for CH (thought of this on my own! think that means I'm getting the hang of BBB). The test was pretty high, around 230 ppm which jives with the city water quality report of an avg 200 ppm calcium carbonate. Oh, and I measured the TA too. It was around 200.

My last test results of the pool were:
FC: 9 (I had just added some bleach and perhaps poorly eye-balled 75floz. Actually, I was just pouring it really slowly and day dreaming about automating my setup )
TC: 9
PH: 7.8
TA: 160
CH: 590 (Yay for rain!! Free calcium free water! )
CYA: 50ish

I think I'm perhaps on the way to proper water balance! I think there might be one or two more drains in my future, depending on how much rain we get today. I thought about trying to get water delivered, but I was concerned their water would be as hard has mine. I honestly didn't call anyone about it, but I'm thinking about it.

So, back to the scaling... Are the dark spots wet spots? Is the reason for the pattern of the water the difference in roughness of the plaster versus the calcium which would lead to the water evaporating at different rates?

Isn't calcium scale white?

Is there any structural problem with scaling, or is it aesthetic only?

Finally, in case anyone was curious about my automation aspirations... My background is as a mechanical engineer (specifically system integration and testing) and IT. I'm thinking I'm going to have to build a micro-pc to put in a cabinet somewhere near the pool equip, probably inside to alleviate cooling issues. I'll likely use some type of NI DAQ for the controls interface. Run both pumps off SSRs (or DFPs, if I decide to go cheap). Probably some type of peristaltic Cl pump (that Stenner model looks nice) for the sanitization. A whole fleet of temperature and pressure sensors. I figure I can determine flow rate using the dP across the DE filter and the pipe diameter. I trying to figure out a backdoor way at measuring (estimating?) Cl, the ORP sensors sound very touchy.

You see, this is what happens when an engineer gets a pool! I've only been in it once since we moved in and I'm already thinking more about automating it than using it!

 

[Richard320]

Sorry for the delay in posting back. Been quite busy trying to finish the final bit of move out from our former home.

I've done two more drain and refills since I posted last. I finally got around to testing our city water for CH (thought of this on my own! think that means I'm getting the hang of BBB). The test was pretty high, around 230 ppm which jives with the city water quality report of an avg 200 ppm calcium carbonate. Oh, and I measured the TA too. It was around 200.
snip

So, back to the scaling... Are the dark spots wet spots? Is the reason for the pattern of the water the difference in roughness of the plaster versus the calcium which would lead to the water evaporating at different rates?

Isn't calcium scale white?

Is there any structural problem with scaling, or is it aesthetic only?:

You would think the scaling would be movie-star-tooth white, wouldn't you? I have very hard tap water too, and very high CH, and was getting some scaling. It isn't rough, yet, just ugly. Keeping the CSI in the negatives and scrubbing with a steel brush has removed some of it. The dark stuff is the scale, the wall beneath is the bright white color!

I don't know if it weakens the concrete any, but I have swam in pools with heavy scaling. It's like sandpaper. Great for removing callouses, but hurts like heck if you're horseplaying and get your knee dragged across it!

 

[frustratedpoolmom]

Jason advised you on how to handle the scale in his post above...

As Richard stated, it's asthetics but it can also hurt like sand paper.

 

[gordiec]

Regarding the automation -- you might consider a salt water chlorine generator (SWG).

 

[himself]

Regarding the automation -- you might consider a salt water chlorine generator (SWG).

I've given it some serious thought, especially since the cost of the SWG and a good Stenner setup is comparable. I've read a few bits about how splash-out from a saltwater pool can affect near-by plant life over the long term. I'm still looking into it and tying to figure out how much of an effect it would be. Our pool is surrounded by flower beds around the back half, and I'd hate to ruin them. I've still got plenty of time to think about it as it will be sometime till I get to that project!

I suppose for now I'll just live with the calcium as it doesn't pose any serious threat to the pool. I've still got to get the water balanced, so that will be my focus for now.

 

[duraleigh]

I suppose for now I'll just live with the calcium as it doesn't pose any serious threat to the pool. I've still got to get the water balanced, so that will be my focus for now.

That is a plan of attack that certainly indicates you have quickly obtained a good working knowledge of BBB. It's puzzling how the previous history of that pool could've gotten the calcium so high but you've done a nice job heading it back under control.

As others have indicated, once you get everything else under control, keeping your CSI down just might start to reduce the scaling. It'll be much easier to focus on that one issue when your parameters are all inbalance. Very nice work! :lol:

 

[himself]

That is a plan of attack that certainly indicates you have quickly obtained a good working knowledge of BBB. It's puzzling how the previous history of that pool could've gotten the calcium so high but you've done a nice job heading it back under control.

As others have indicated, once you get everything else under control, keeping your CSI down just might start to reduce the scaling. It'll be much easier to focus on that one issue when your parameters are all inbalance. Very nice work! :lol:

I'm pretty sure I know how they got it so high. They previous owners were devote followers of the Leslie's method. Trichlor pucks for chlorination and cal-hypo for shocking every few weeks. Based on the CYA level and CH level, I would assume they never drained the pool in the two years it's been in the ground.

I'm pretty sure that the guy at leslie's was doing the CH and CYA test wrong (well, not very accurately anyway). He said my starting CYA was 100 and the CH was 750, but based on my numbers and the math I did on the 3 drain/refils, I believe my starting values were closer to CYA 100++ (maybe 130?) and CH 900+.

 

[svenpup]

It's kinda late since you look like you are already well under way, and I am surprised that simicrintz hasn't already chimed in, but Reverse Osmosis service (if it is available in your area) is an option for getting levels (CYA, CH, TDS, etc) down. This is especially helpful if your fill water has high levels too.