pink algae and other problems

[matthew64]

So I have been keeping the FC at around 20 (as high as 24) for several weeks now, have brushed and vacuumed the pool multiple times and yet the pink stuff still returns. it mostly appears as more dead particles on the bottom of the pool, but there is new formations on the walls. Im worried that Im creating the most chlorine resistant super bug ever.

[PoolDoc]

Hm-mmh.

My problem is that I have ZERO personal experience with pink algae (it's not actually algae), and very little information about what might be most effective. Complicating the issue is that it is an opportunistic biofilm community that's going to tend to stick around in cracks and crannies even after it's 'all gone'. So, you not only need to get rid of it, you're going to have to keep getting rid of it.

What do you want to do?

Option #1: I looked at your pool online (Google Maps has a very nice image of it!). Since you've got no steps, you can probably drain to 8" deep in the shallow end, without too much risk. That will give you about a 60% drain, reducing your CYA to ~140 ppm. Then you can refill and treat with high chlorine. You can also go to 60 ppm borates, which may, or may not help but will reduce your pool's susceptibility to true algae.

Option #2:Try chemicals till you find what will work. I suspect the cheap quat algaecide at Sams Club will work . . . if you add enough to make your pool soapy and THEN brush. You'd only be out $30, but your pool will be soapy and probably irritating to eyes for maybe 2 weeks. You could try polyquat which is more expensive, and may not penetrate the biofilm well, though it might help if used at the same time, as the other. You could use ammonium chloride, to produce monochloramine which penetrates biofilms MUCH better than regular chlorine . . . but monochloramine is irritating.


Honestly, if it won't bust your budget, I'd probably try this in your shoes:

• Do a 50% drain (8" water in the shallowest stpot) and replace => $###?
• Add 60 ppm borates (19 boxes of 20 mule team, plus maybe 6 gallons of muriatic acid => $100)
• Add 1 pint of polyquat and brush every 3 days for 2 weeks (3 x $20 => $60)

If that doesn't work . . . you can move on to the foamy quat + monochloramine. But the first 3 steps are all stuff that's generally good for your pool, ANYHOW, so there's no waste. And, none of that will put your pool out of service, except for the time it takes to refill.

One BIG caution: do NOT do this if the ground around your pool is wet! If you're not sure, dig a post hole next to your pool. Let it stand overnight. You can drain to 1 foot ABOVE the highest water level in the hole.

[chem geek]

I'm unclear about something. The HTH Spa Non-Chlorine Oxidizer Tablets that were added are potassium monopersulfate (MPS), not bromine or bromide. I don't see where any bromine has been added to this pool. Bromine is often effective at killing pink algae and especially so in this situation since the CYA is so high that chlorine is simply not going to do the job (unless there is significant water dilution first to lower the CYA level). So adding some sodium bromide to the pool will, when activated by chlorine, produce bromine to kill the pink algae.

[PoolDoc]

I'm unclear about something. The HTH Spa Non-Chlorine Oxidizer Tablets that were added are potassium monopersulfate (MPS), not bromine or bromide.

@ Chem_Geek: Thanks for catching that, Chem_Geek. I didn't follow the link -- I just saw that they were tablets and assumed that it was bromine. So that's new info for me, that MPS is being formed into tablets. I see why he THOUGHT they were bromine: apparently they are intended as a MPS + bromide spa system, and are labeled that way.

@ Matthew: The fact that you do NOT have bromine means you can try that, as an option. Adding 1.5 ppm bromide to your pool -- 1/8 of a 2# bottle -- might help. If you want to try it, here are a couple of links:

Nava Chemicals 652072097 Yellow Algae Remover, 2-Pound Bottle @ Amazon
Tropi Clear TC-4402-1 2-Pound Yellow Eliminator @ Amazon

It might be a good thing to try, even if you do drain. Adding the bromide before you drain might allow you to get a lot of it cleaned up, BEFORE you drain. Using it in conjunction with the foamy algaecide might well allow you to eradicate it, and then remove 50% of the algaecide and bromide, so it wouldn't take to so long to get rid of them otherwise.

[matthew64]

Thanks for the replies. I think I sent the wrong link for the bromine tablets. I am 99% sure that it was brominating tablets (at walmart). The link I sent looks similar, but I was looking for bromine specifically and Im really pretty sure thats what I bought and put in the pool (x3). Thanks for looking up my pool, its cool(and sort of creepy at the same time) you can do that on google maps (that picture was taken the day of my birthday last year). I do have steps in the lower left corner of the pool in the shallow end. does that effect if I can drain down to the deep end?

So Im pretty sure it was bromine tablets. So my options are try a foamy algaecide and maybe something like yellow out. I found pink treat which seems to be just really bromine. http://www.swimpool.com/PinkPoolAlgae-pinktreat.htm. We also have been having to add water every week because its been so hot. If I had to add it up its probably been maybe 2ft of water loss that may have brought the cya down some (havn't checked it recently)

[aylad]

Water loss due to evaporation won't bring your CYA down--it just concentrates the CYA in the remaining water in the pool until you refill, then the refill just dilutes it back to the same level it was before the evaporation. If you're wanting to bring the CYA down, it'll have to be done by water actually removed from the pool--splashout, backwashing, draining to waste, etc.

Janet

[matthew64]

Thanks for that piece of info. So can I safely drain half my pool even if I have steps into my shallow end? Also any thoughts on "Yellow Out" vs "Pink Treat"