Black Algae

[Swimgirl]

It seems that the roots for black algae grow through the waterproof liner!! I've replaced liners with BA and found it to be in the floor in the same areas as the spots on the liner :? We treat the effected areas of the floor with 12.5% liquid chlorine - sometimes it works/ sometimes it doesn't -- It's my belief that the ones that it doesn't work for aren't maintaining their FC - but my customers lie about maintaining their pools:!:

Thanks for the idea of using the pressurewasher to 'knock off' the heads

Mmmhmmmm....my algae (?) grew when I was using the Frog and held the recommended 1ppm FC....

Gee, they say that the frog's okay when you keep the chlorine down to .5. No wonder, when I first got my pool and the froggy, the salesman also sold me the Frog Bam (the copper based algae preventative) with the frog, saying that out here, everyone gets algae without an algae preventative. (No kidding, he really said that.) But at least no one has gotten green hair, but there is a ring around my pool at the water line due to the copper in the Bam and the metals in the froggy! I'm going to take care of that as soon as I get a chance, maybe this weekend.

 

[waste]

So yeah, we use ordinary bleach.

Unless you can find the pool store concentration at a cheaper $/%/gal

(Great post Ohm_boy -- and AzW - I love the 'down home' similies 8) )

 

[frustratedpoolmom]

It seems that the roots for black algae grow through the waterproof liner!! I've replaced liners with BA and found it to be in the floor in the same areas as the spots on the liner :? We treat the effected areas of the floor with 12.5% liquid chlorine - sometimes it works/ sometimes it doesn't -- It's my belief that the ones that it doesn't work for aren't maintaining their FC - but my customers lie about maintaining their pools:!:

Thanks for the idea of using the pressurewasher to 'knock off' the heads

Mmmhmmmm....my algae (?) grew when I was using the Frog and held the recommended 1ppm FC....

Gee, they say that the frog's okay when you keep the chlorine down to .5. No wonder, when I first got my pool and the froggy, the salesman also sold me the Frog Bam (the copper based algae preventative) with the frog, saying that out here, everyone gets algae without an algae preventative. (No kidding, he really said that.) But at least no one has gotten green hair, but there is a ring around my pool at the water line due to the copper in the Bam and the metals in the froggy! I'm going to take care of that as soon as I get a chance, maybe this weekend.

Don't get me goin' bout that darn froggy

 

[Aquaman95]

Saw that at Warehouse. Dumb question - is liquid chlorine the same as bleach ? Realize it is twice as strong but is it absent the "additives" the trichlor pucks do ?

Thanks

All the Warehouse locations have it. I don't recall if it's 12.5% or 10.5%, but it is very good quality bleach that's made right here in Houston.

$3.50 per gallon is a bit steep though...catch a sale at Kroger/Wal-Mart and you're in better shape with generic laundry bleach.

 

[AzWildcat]

First - Ohm_Boy - Thanks for the simplification and clarification. I needed that. Also, please let me know if they ever make Sodium Hypochlorite in liquid form, whether it be bleach, chlorine, or shock.

On the serious side - Will be draining pool half way (to reduce CYA and make the BA "head" removal process a little easier) tonight. In the morning I will be pressure washing and brushing the dreaded Black Algae while the pool is filling up. It will be neccesary to be in the pool to do this. Needless to say, my CYA will be in flux and dropping as I fill the pool up. However, as soon as we are done brushing and washing and while the pool is still filling, I want to heavily "shock" the pool with bleach to start the root kill process as soon as possible. Assumming this process makes sense I have several questions.
1) I used the Pool Calculator and guessimated what I think my CYA will be when done and calculated how much bleach I will need at full capacity to get it to the Yellow\Mustard shock. However my CYA will be in flux. It will in fact take the pool way over that min while it is filling up. Is that OK ??? - to exceed the Yellow\Mustard shock values ?? Or is that an off shoot of the Marilyn Monroe medicine dosage approach to taking a short nap - If two work - twenty works 10X better ? Can I do damage to anything by over bleaching ?

2) Does anyone have a clue how time I have between brushing and blasting the BA before the heads start to harden ? Have figured out it is probably not a good idea to be working in a pool that has a min. of 23.8 ppm of chlorine.

Thanks

 

[waste]

I don't see any harm in slightly overdosing the pool with chlorine while you are in flux and refilling - if you had a liner pool, it'd be a different story - GO FOR IT and kill that stuff. (I wouldn't suggest swimming or wearing a $100 bathing suit while the levels are so high - but I would go in it - you probably shouldn't -- I do a lot of things I tell pool owners never to do )

 

[AzWildcat]

Ok - Drained the pool and killed off abot 80% of the Black Algae. Couple of questions
1. Is it "normal" to have some spots left over - more resilient ?
2. Know that should keep chlorine levels above the Mustard algae shock zone for my CYA level for about a week - Should I run my pump, DE filter, and Polaris 24\7 while I am at the high chlotine level and brushing 2x a day ?
3. Know that my pH reading is invalid while at high chlorine levels - should I make any "assumptions" about pH level ?
4. What other water element is critical during the high CL level time ?

Thanks

 

[frustratedpoolmom]

I think the mustard shock level is a 24 hour thing, not extended periods, can damage the pool surface, vinyl or plaster.

If you brush the resistant parts during the high levels, they should die off, it may take a repeat or two, letting the FC drop in between. You may have some left over staining, if it's a plaster pool an acid wash next time it needs resurfacing should remove any residual stains.

 

[AzWildcat]

Mom - So the black spots I am seeing ( which are not as black as they once were ) may be stains ?

Have had the pool at VERY HIGH levels for 3 days - is it time to drop it down ?

 

[frustratedpoolmom]

Mom - So the black spots I am seeing ( which are not as black as they once were ) may be stains ?

Have had the pool at VERY HIGH levels for 3 days - is it time to drop it down ?

I would let it drop down to regular shock level, and hold it there. Keep scrubbing at them, once or twice a day.

It's hard to say if they are stains. I was told the stains in my pool (at the time) were Black Algae, unusual for a vinyl liner, supposedly. (This was a pool store "expert" that said BA.) So based on his advice at the time, I treated for BA. Every time I let the FC drop, the stains returned. Now this was in my pre-TFP and BBB days....and my recommend Pool Frog FC level was 1ppm no wonder they came back, right?

So after discovering BBB, I tried the "FC hold overnight, no loss of FC, algae dead". Three nights in a row, the FC held, no drop. Not a live algae stain was my conclusion. I was told by the pool store liner replacement was my "only option". I chose to live with it.

But I can still see them, very faint, in the same spots, and when my FC drops to minimum they are more noticable. I'm more careful now and I don't let it drop. But when I returned from vacation last week my FC was about 1 and low and behold there they were, a bit more pronouced.

Now, I have heard of a mold type fungus that can grow under AGP liners in the sand, and they seem to react the way mine have. So I'm not real sure if what I had was BA at all or this mold/fungus. Interestingly the stains are not there at the start of the season. They appear as the sun is more strong and the water is warmer.....I'm more convinced of a mold/fungus.

But because of my experience I have read quite abit online about BA. I have heard it can leave stains behind. And I have heard that if you can't get rid of it and you have a plaster pool, the eventual required resurfacing or an acid wash should take care of it.

In any event, since it's a fresh outbreak (mine have been around for 4 years), I would keep your FC at Schock for at least a week (normal shock, not Mustard level) and keep scrubbing at those resistant stains). When your FC drops to normal target, if they reappear, it could just be residual staining or they're not completely dead, and you have to repeat the process. I would think a week of shocking/scrubbing would kill the little buggers.

I hope this helped, but I know the only thing that would really help is for the spots to be gone, right?

I hope you were taking pics along the process. We love pics.

 

[AzWildcat]

Once, I get this Black Algae under control, it looks like I'm going to have to keep my FC above 6.1. Is the OTO test method in the TP Test kit the best way to accuratley measure FC ?

 

[frustratedpoolmom]

Once, I get this Black Algae under control, it looks like I'm going to have to keep my FC above 6.1. Is the OTO test method in the TP Test kit the best way to accuratley measure FC ?

To know for sure the best way is the FAS-DPD (the powder that turns the water pink and then the drops that turn it back clear). But you can go with a really dark yellow on the OTO test and know that you around 6.....

 

[Denali]

Mom - So the black spots I am seeing ( which are not as black as they once were ) may be stains ?

Have had the pool at VERY HIGH levels for 3 days - is it time to drop it down ?

Once you get the heads off the BA it will be lighter. It is still BA but is now easier to kill. Depending on how many spots you have left, it is effective rubbing a tri-chlor tab against the BA. That puts the chlorine right where you want it.

One thing I have done with BA is use my pocket knife to gently scrape it off. Mask and snorkel optional.

 

[AzWildcat]

Have been running the pool at very high chlorine levels to kill the dreaded Black Algae. Kill done. Will now bring pool down to the chlorine level in line with CYA\Chlorine chart. I will be switching over to the BBB method once I am there. It is my understanding that none of the tests, except the chlorine tests, are accurate when a pool has the anount of CL we have been keeping in it for the past week (about 45-35ppm). Further understand that 10ppm is kind of the magic point at which pH, CH, & TA tests become accurate. Our CYA is about 20ppm as we drained about 2\3 of the pool.

What is the first, second, etc "element" - water chem component to bring into line when I reach the point where tests are accurate ???

We are in Texas and it is hot. It is a 25,000 G gunite pool.

Thanks

 

[frustratedpoolmom]

Have been running the pool at very high chlorine levels to kill the dreaded Black Algae. Kill done. Will now bring pool down to the chlorine level in line with CYA\Chlorine chart. I will be switching over to the BBB method once I am there. It is my understanding that none of the tests, except the chlorine tests, are accurate when a pool has the anount of CL we have been keeping in it for the past week (about 45-35ppm). Further understand that 10ppm is kind of the magic point at which pH, CH, & TA tests become accurate. Our CYA is about 20ppm as we drained about 2\3 of the pool.

What is the first, second, etc "element" - water chem component to bring into line when I reach the point where tests are accurate ???

We are in Texas and it is hot. It is a 25,000 G gunite pool.

Thanks

I believe PH (and TA, since they are related) and then CH. I know with plaster you have to be careful so I'm not 100% certain. So hopefully the experts will chime in. Lastly the CYA, if it's down to 20 the CL should drop rather rapidly. Consider adding that too, since it's an acid it will also adjust the ph, if the ph needs adjusting. Make sense?

Good news about the spots When do we get to see pics? I hope you did a before and after.....