To drain or not to drain?

[brcp40]

Hi,

I recently purchased a new home with a 16,000 gallon salt pool/spa (plaster/pebbletec finish).

FC - 5.0
CC - 0
Salt - 2600
pH - 7.6
TA - 90
CH - 600
CYA - >100
Phosphates - 350ppb

The chlorine generator is a ClevaChlor RP30HD, which recommends a salt level of 2250-2750.

The filter is a Sta-Rite System 3 cartridge filter.


Due to the high CH levels, the pool store guy (as well as the pool company I had inspect the pool prior to buying the house) suggests draining and refilling. The water here is relatively hard, so I had them test my available fill water as well -- 160.

The CYA level is also "too high," but they can't tell me by how much since their test caps out at 100ppm. This was another reason they gave to drain.


The pool was built in 2004, and I have no idea if it has been drained previously (or how well things have been maintained beyond what I can see now).


The first question is whether or not I need to drain. My feeling is yes, since the CH levels are only going to go up from here.


Second, supposing that I do drain and refill, in what order do I need to set things up? What I have surmised so far is something like this:

- Add salt to the high end of the range
- Adjust pH and TA
- Add CYA to ~75ppm
- Start the SWG
- Adjust SWG to achieve FC of 3-5ppm


Do I need to do something to get some chroline built up in the water between the time that I fill it up and the time that I start the salt system (salt, pH, TA, and CYA all at proper levels)? How long should I expect it to take from the time that the water level is good until I can fire up the salt system and let things level out?

I also plan to replace the filter cartridges at the same time -- I scrubbed them last weekend, but it's apparent that they have not been cleaned in a long time.

Lastly, do I need to rent a submersible pump to drain the pool, or can I use the pool pump to do most of the work? The Sta-Rite filter has a drain, which is plumbed to a drain pipe. I "think" there is a main drain at the bottom of the pool, but I am not 100% certain... there are 4 fixtures at the bottom of the pool (identical), all of which look like drains. There's a valve on the return line for the pool that enables "floor heat," so I assume that is what at least some of those fixtures are for. On the supply side, I have a valve to select between pool/spa. On the pool side, there is another valve to select between the cleaner (hayward pool vac ultra) and the skimmer. Those are the only selections I have on the supply side, so I'm not sure if a drain might be tied in with the skimmer or cleaner line.


Thanks,

-Bill

 

[linen]

Welcome to tfp Bill

First you are going to need your own accurate test kit...pool store tests are notoriously unreliable. See links in my sig for testkits. Assuming the results you have are accurate you will need to do a partial drain particularly because your CYA is probably much higher than the measured 100 ppm. I would not do a full drain for a couple of reasons: 1. You do not want to float your pool, which can happen if you have a high water table(where do you live?). 2. Although your CH is high I think you can manage it especially since your TA is low and if you actively keep your ph closer to 7.4 than 7.8...other than CYA your test numbers look very good. Ignore the phosphates, if you keep FC in the proper range, then phosphates will not be a problem.

I would probably replace 30% of your water and see where CYA (and CH) end up. Chances are you may have to do another partial drain and refill, since I guess (and I think you do too) that your CYA might be quite a bit higher than 100 ppm, but we won't know until we can get it below 100. Of course to do this you will need an accurate test kit.

Make sure you read Pool School (see link in my sig) there is a lot of info in there!

 

[supertune]

Hi Bill and welcome to TFP!
Take pictures of equipment pad and pool drains, might help to answer your valving questions.
Yes, for sure you would want your own test kit...
See the bottom of my sig.
All the info you need will mostly be found in the Pool School link at the top of the page.

Chuck

 

[Linkterfur]

Welcome to tfp Bill

First you are going to need your own accurate test kit...pool store tests are notoriously unreliable. See links in my sig for testkits.

Here is an example as to what my local pool company once told me... I tested the water before and after (within an hour and a half) just to see how accurate it was... It wasn't even close. The way they test water is they take a test strip and use a machine that somehow reads the colors. Notice how they say the CYA is suggested at 30-200 ppm? What a joke. Do yourself a huge favor and use a testkit and test yourself, you won't regret having that soon to be clear pool afterwards.

Anyway if you find you have a higher CYA and CH, do a partial drain.

http://i1260.photobucket.com/albums/ii5 ... titled.jpg

 

[brcp40]

Thanks for all of the great feedback. I do have a test kit, but it's just a more basic Taylor kit that does pH, TA, FC/TC. I've ordered a TF-100 and some salt test strips, so I'll get going with that when it gets here.

I'm in Southern California, so I don't think we're at too much risk for having the water level be up as high as the bottom of the pool...but better safe than sorry. Next weekend (or later if I don't have the test kit yet) I'll drain out 30%-ish of the water and refill to see where that gets me. I'll go pick up a couple of bags of salt to mix in when the pool is filling back up to keep that at the appropriate level. I assume that with only a partial drain and clearly plenty of CYA (and salt, since I'll be adding some) that I do not need to shut down the generator as I would with a complete drain & fill, correct?

Thanks again!

-Bill

 

[Richard320]

Now that we know where you are...

If you're anywhere near Escondido, there is a reverse osmosis outfit that can clear out your pool without losing water.

Otherwise, it's drain and refill. You'll be able to get the CYA down, but the Calcium will go back up. Trust me. Our water is just too hard. There's supposed to be rain this weekend, so do what I do: aim a downspout at the pool. Free water, Calcium-free! CYA-free, too.

 

[PSW]

There's supposed to be rain this weekend, so do what I do: aim a downspout at the pool. Free water, Calcium-free! CYA-free, too.

Great idea, Rich!

 

[mas985]

You could try what I call an in place refill. I have done this pretty successfully has decribed in this thread.

 

[carlscan26]

I'm in Southern California, so I don't think we're at too much risk for having the water level be up as high as the bottom of the pool...but better safe than sorry. -Bill

Bill, don't count on that - I'm in SD and have a high water table in my neighborhood - in fact I'm above an underground stream! Just a few miles away where we lived before we had no ground water issues...you need to know for sure so unless you do stick to your current plan to not be sorry

Pool Services Technologies covers a good bit of So Cal and the system works great as advertised. It's a bit more expensive than a drain and refill if you do everything yourself. If you use a pool maintenance company then the RO process is definitely cheaper. Don't know if you're in a water restriction area and/or hate the thought of draining 8K gallons of water so that can factor into your decision as well. There is no one right answer though so good luck!

Fill water with CH of 140 isn't actually all that hard and it will take some time for it to get high. As linen said, it's still easily manageable at your current level if you keep an eye on pH and TA levels. Keep an eye on your CSI levels in the pool calculator and you'll be fine.

If you do use rain water form your roof, run it through some kind of sediment filter - at the very least a woman's stocking to keep all the dirt from your roof from going into your pool.

 

[brcp40]

Thanks for the tip on Pool Services Technologies... I'm going to get an estimate from them. I have two $500 estimates from late last year (when we had everything inspected before buying the house) to drain/refill/setup chemicals. If it's that simple, I'd rather just do it myself ... but if I can save the trouble of draining the pool (and buying more water to replace water that I threw away) I'm all for it.

 

[Ohm_Boy]

I have a friend in Temecula who said it was more cost-effective for him to buy a pump from Harbor Freight because of the periodic need for drain/fill of his pool. He had been renting a pump prior to that. Most of his issue comes more from CYA creep due to trichlor use than from CH problems, but the fix is the same. I'd like to know what the cost/rates are for RO

 

[linen]

There's supposed to be rain this weekend, so do what I do: aim a downspout at the pool. Free water, Calcium-free! CYA-free, too.

This statement brought a question that has been sitting in the back of my brain to the front :

Here in MN most of us have asphalt shingle roofs. Is there stuff that we could be adding to the pool in concentrations we do not want due to the rainwater running in thin sheets over the exposed aggregate and tar that we might not want in our pools? My fill water (well water) is very high in TA and iron. We get plenty of rain (usually), so if I used rain barrels I could probably make up the water I pump out when backwashing my sand filter.

 

[Ohm_Boy]

I'd guess that your big concerns would be aggregate and organic bug/bird/tree droppings. The aggregate could be filtered out, the organics can be handled by chlorine.

 

[linen]

Okay...to derail Bill's thread a bit more (sorry Bill), I suppose one could pre-treat the rain water barrels (plastic I assume) with chlorine, if the water is not needed immediately after the rain then use the sand filter to filter (maybe with a sock as a pre-filter)....hmmmm...I think I might start this process this spring to fill my pool from the winterization drain, I needed an excuse to get gutters on the back of the house anyway...erosion and water in the basement was just not enough....but low TA and Iron...I'M IN

 

[carlscan26]

I'd guess that your big concerns would be aggregate and organic bug/bird/tree droppings. The aggregate could be filtered out, the organics can be handled by chlorine.

X2! I tried a quick search and didn't find it but I know Richard320 has mentioned this before about gettting dirt and such in his pool from the rainwater off his roof. Anyway it's easy enough to solve.

 

[brcp40]

For those who were interested.. I got a quote back from them of $425 for my 16,000 gallon pool. There's a $25 off coupon on their site as well.

When they are done, pH, TA, and calcium will be good (they guarantee CH < 200). If they clean out too much CYA they will add some back. I'll have to provide salt and enough chlorine to get the initial level set... So, question: what is the best method to add this initial chlorine without increasing the CYA and CH levels that I will have just paid to reduce? I figure I should add enough chlorine to get up to ~3 ppm and then let the salt system take over and make up the rest.

Thanks,

-Bill

 

[Ohm_Boy]

Liquid chlorine (sodium hypochlorite) does not add CYA nor calcium. You may find it in 12%-12.5% strength as "liquid shock" from pool stores, but you can always find it as 5.25%-6% bleach. Make sure you get the regular unscented stuff. The Pool Calculator (link in my signature) will tell you how much you will need.

 

[Richard320]

There's supposed to be rain this weekend, so do what I do: aim a downspout at the pool. Free water, Calcium-free! CYA-free, too.

This statement brought a question that has been sitting in the back of my brain to the front :

Here in MN most of us have asphalt shingle roofs. Is there stuff that we could be adding to the pool in concentrations we do not want due to the rainwater running in thin sheets over the exposed aggregate and tar that we might not want in our pools? My fill water (well water) is very high in TA and iron. We get plenty of rain (usually), so if I used rain barrels I could probably make up the water I pump out when backwashing my sand filter.

I have asphalt shingles as well. They've been baked to a crisp in the sun, so I get no oil sheen. I do get a lot of grit and a lot of fine dirt.

My technique is to empty the spa into the pool when it's going to rain, then start pumping the pool out. By observation, I figured that the roof area that drains into this particular downspout works out to about 3X the rainfall. So if they predict 1" of rain, I can expect to see my pool rise 3" and pump it down accordingly. Then I set the valves so the spa isn't getting any circulation. After a rain, the pool usually looks okay, the spa is pretty dark and evil looking. But, it's easy to clear. I'll move the valves to suck from spa and fill pool until it starts coming over the spillway, then switch things to filter spa only. By brushing to keep everything in suspension while it's filtering, I can get it clear in about 20 minutes. The I reset everything back to normal. I usually give it an extra shot of bleach to take care of all the organics that washed in from the roof.

 

[Smykowski]

I had been thinking about this for awhile, and after seeing that Richard does it, I figured it's not such a crazy idea after all.

Over 50% of my water bill is sewer charges, and I'd rather not pay that. So, I did the math and figured it's $9/1000 gal.

My pool works out to roughly 500 gal./inch. If I raise my level a foot, I'm at $45 in water charges. Menard's has 3" solid drain tube on sale this week ($25 for 100'), and I'll use the other half for another project.

$13 for tubing, $4 for the downspout adapter, $5 for bungee cords to hold it in place, and an old nylon rubber banded around the end to strain out the big stuff. Under $25 for unlimited free water seems like a pretty good deal to me.

 

[Richard320]

Finally it's raining!!

The flex tube baffles catch a lot of the shingle grit.
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