High CYA - HIGH Phosphates

[austinnichols101]

This is my first pool and it'll be a year in April. It's a 17 x 35 (approx 18,000 gal) diamondbrite located in Miami, FL. I refill the pool from my well pump. The pool is open basically year-round and I believe that the previous owner was using chlorine tabs w/stablizer for the most part.

I've been struggling to maintain the chlorine levels in the pool and more often that not I test and there's little to no FAC/TAC.

I went into my local Leslie's for this first time this weekend (I had been using another store that's closer) and here's what the water analysis form says:

FAC X
TAC 0
Bromine X
PH 7.8
TA 110
Calcium Hardness 240
CYA 100
TDS 1600
Copper / Iron X
Phosphates 2500
Salt X

What obviously stands out are the Phosphates and the CYA. Leslie's reccomended 36oz PhosFree followed by 6oz copper algaecide, then 1 qt acid and finally 3 chlor brite packages and 3 fresh-n-clear packages.

I've successfuly maintained a saltwater aquarium for a number of years. Once I understood the basic cycle (thanks Martin Moe), it wasn't that much of a challenge. However, I've had a difficult time understanding the dynamics of what's happening with the pool.

 

[JasonLion]

Welcome to TFP!

I would not worry about the phosphates. For the most part when pool stores sell phosphate remover they are simply trying to separate you from your money. There are some specific, and rare, situations when phosphate remover can help. It doesn't sound like any of them apply to you.

Second, avoid copper based algaecide. You do not want any copper in the water. Copper can easily stain the pool and while it does help fight algae there are better ways to deal with algae without the problems copper can cause.

It would be a really good idea to try and get your CYA level down below 100. With CYA that high there will be several challenges, not the least of which is that you need to keep your regular FC level above 8, preferably 10-12. Fighting algae can require FC levels around 25 or higher. Problematically, many of the tests read CYA at 100 even when it is far higher. That means there is a chance you have an even more substantial CYA issue. The only practical way to lower CYA is to replace water.

The best investment in your pool you can make is to get your own high quality test kit. I suggest the TF-100, see the TF Test Kits link in my signature. The Taylor K-2006 is also good. Without the FAS-DPD chlorine test in those kits you will have a very difficult time fighting algae. Plus, doing your own testing is almost always more reliable than going to a pool store.

Now would also be a good time to start reading some of The Stickies, see the link in the sub-heading of every page. You can find some good tutorials and background on the BBB method there.

I suggest switching to bleach as a chlorine source. Chlor-brite has CYA in it, which you don't want any more of. Fresh 'N Clear is a non-chlorine shock, which is alright but more expensive than bleach.

Of all the pool store recommendations, the only one I really agree with is the acid. You need to bring the PH down a little. Then you need to add a substantial amount of chlorine and see if you can hold a chlorine level. If you can't hold a chlorine level you are going to need to shock the pool till you can hold a chlorine level. With the CYA level that high shocking will require lots of chlorine, which is where some non-chlorine shock could help though it will be more expensive.

This whole process might take a little while. Break it into manageable chunks and do some reading while you are at it. Start with the acid, see if you can get the PH down to between 7.3-7.5, think about getting a good test kit, and start stocking up on bleach (unscented 6%). If you have more questions feel free to ask!

 

[duraleigh]

Hey, Austin,

Welcome! I'm simply posting for reinforcement..............Jason's advice is right on the money....particularly about getting the CYA down. It'll really simplify your pool maintenance.

Secondly, it sounds like your not anticipating your chlorine demand. It's very normal for most pools to consume 2-3ppm daily in chlorine so you must add enough to keep up with that demand. As Jason said, avoid trichlor pucks or any other source that will continue to add CYA to your pool.

 

[austinnichols101]

Thanks for pointing me in the right direction - water change in progess <g>...

I'm going to go through the BBB information this evening.

One question at this point - how does Clorox compare with the yellow jugs? I understand from your post that Clorox is cheaper in the long run. Is the per-gallon chlorine content comparable?

 

[duraleigh]

I'm not sure what you mean by the "yellow jugs" The clorox many of us use is 6% unscented Clorox and is not so much cheaper but READILY available (grocery store, K-mart, etc.).

Are the "yellow jugs" pool store chlorine? if so they're probably 10 % chlorine or so and, if it's convenient to get, can frequently be a better deal than Clorox.

 

[austinnichols101]

Sorry - the 'yellow jugs' are the pool store cholrine that I've been purchasing. It seems that there's a pool store on every corner in Miami - there are 3-4 within a mile of my house...

That being said, I was able to pick up several 174 oz jugs of Publix brand ultra bleach (6%) for $2.65 each. If I adjust that out it's the same as a gallon of 8% (minus the extra water). Picked up a box of A&H and a box of borax for good measure.

I'll let you know how the pools store compares as I have to go over in the AM and get some muriatic acid.

I let out about 40% of the water and am in the process of re-filling. Gotta grab a test kit tomorrow to get a new baseline now that I've changed so many variables.

 

[Guest]

!!

If you are going to get a testkit I would strongly recommend the Taylor K-2006. Or order the TF100 testkit from Duraleigh! It uses the same Taylor regents but is a better 'bang for the buck', IMHO. The two kits are almost identical but the TF100 has a wider range ph and more CYA reagent and a better CYA view tube but does not include acid and base demand tests (not that useful except in special cases). It also includes and OTO test for quick daily monitoring of chlorine levels. Do not get the Taylor K-2005, it has some limitations.

Don't know the going rate on pool chlorine in Miami but up here in St. Augustine it's a better deal than bleach. BTW, what part of Miami? I grew up in the Gables. Also been keeping Reef and Marine tanks for over 30 years now. Was a member of the Marine Aquarium Society when I lived in S. FL.

Do your own water testing. You can do a better job than most of the pool stores around, expecially if you have experience testing a marine tank! Some of the tests (such as calcium hardness) are identical!

Ignore the phosphates and stay away from the copper. Getting the CYA down is the first step.

 

[austinnichols101]

I'm definitely going to order the TF100. Leslie's already has enough of my money.

Here are today's numbers:

FAC X
TAC $
PH 7.4
TA 12
CH 320
CYA 60 !
TDS 1100
Copper / Iron -
Phosphates -
Salt -

Looks like the water change had the intended effect!

I'm about a block South of the Miami-Dade College South campus. My office is over by the Gables. I was into the aquarium scene for about 15 years until last year when I moved to the new house. I have a 92 all-glass corner tank sitting in the garage just waiting to be set up again. I was planning on trying an algae filter this time instead of a wet-dry. There's a guy down here who's been running one for the past couple of years and it looks great.

Chlorine is definitely cheaper than Clorox down here. I checked this AM and 2 1/2 Gallons of 10% are $2.99.

THANKS TO EVERYONE FOR THE GUIDANCE! I printed out the stickies and went through them last night and I finally feel (relatively) comfortable with what I'm doing now.

 

[JasonLion]

Congratulations! Your numbers are looking a lot better. Hopefully the TA of 12 is either a typo or a bad test result. The acid and water replacement would have changed, probably lowered, the TA but they couldn't have brought it down that low.

The next step is to try to maintain an appropriate FC level. With CYA of 60 you want to aim for a FC level that never goes below 5. Depending on how much sunlight you get that might mean bringing it up to somewhere around 8 to 12 in the evening so that it is still at least 5 the next evening before you add more chlorine.

 

[austinnichols101]

Jason,

Yeah - the TA on yesterday's test was 110 and today it was 12. I ordered the TF100 so as soon as I receive it I'll post what the actual turns out to be. I believe the higher number as the pH has historically been very stable.

I'm considering another 30-40% change at some point in the future to drop the CYA down to 40. However, now that it's closer to what it needs to be I'm going to wait a couple of weeks and see how the numbers work out.

Leslie's had a great pitch today on their Cal Hypo 'powder plus'. The salesperson was touting how it was better than the liquid chlorine becuase it was 73% and didn't lose strength. No mention of what it does to the CAL over time. I just nodded and said 'thanks - I'll check it out next time'. Knowledge = power.

I'm also thinking that a liquidator may be in order but again I need to do things manually for a while to understand what's happening.

 

[Guest]

I was into the aquarium scene for about 15 years until last year when I moved to the new house. I have a 92 all-glass corner tank sitting in the garage just waiting to be set up again. I was planning on trying an algae filter this time instead of a wet-dry. There's a guy down here who's been running one for the past couple of years and it looks great.

Wet/dry filters are just nitrate factories. I gave up on them years ago in favor of plenum live sand filters after playing around with denitrators. Refugeriums and algae filters will work at reducing nitrates also as long as you harvest the algae on a regular basis. If you are not going to overstock the tank or you are setting up an invertebrate or reef tank then a plenum is the way to go, IMHO! (Sorry for the off topic post!)

 

[JCJR]

Welcome to TroubleFreePools.

I also live in Miami and not too far away from you. I live close to Robert Morgan Voc on 184st

Pool store bleach runs about $3.99 for 2.5 gals of 10.5 % (I think the percentage can be +/- .5%). The price of $2.99 is a special Leslies is running but normally 3.99 which is still better than regular bleach.

I frequent the Leslies on US1 and 142nd. I have a Liquidator and so far so good. I've had it three months and I think it has been the best money spent. I have added 2.5 gal of CL every 1.5-2 weeks with the Liquidator. I'm sure it is due having the pool covered (not the temp because my water is 80-84 deg).

Defenitly get your own test kit. The pool stores are very inconsistent and can drive you crazy with their wrong information both testing and advice when first starting out. I have learned so much from this forum that in no time you to will feel confident and will be able to know your own pool better than anyone.

 

[chem geek]

FYI. For Cal-Hypo, for every 10 ppm FC it adds, it also adds 7 ppm to Calcium Hardness (CH). For Trichlor pucks/tabs, for every 10 ppm FC it adds, it also adds 6 ppm to Cyanuric Acid (CYA). Given your already high enough CH level, it was good for you to pass on the Cal-Hypo. You can just use chlorinating liquid.

By the way, the unusual chlorine demand you were seeing was algae that was trying to grow -- the high CYA level you had made the chlorine less effective so the algae was able to grow fast enough to consume chlorine at a noticeable rate.

Richard

 

[austinnichols101]

I also live in Miami and not too far away from you. I live close to Robert Morgan Voc on 184st

Yes - you're definitely very close. I'm about a block south of the Miami-Dade College campus near 117th Ave. BTW, did you ever get your solar?

 

[JCJR]

Yes, I got my solar 3 months ago and have been enjoying 82-88 deg temps since THanksgiving.