Can I use an algaecide in a bromine pool? When to empty a bromine pool?

[QPSUtah]

Have a client that has a small bromine therapeutic pool (5000 gallons). It has a green discoloration. I'm new to bromine, but have spent a couple hours researching it on this forum today. Seems like the recommendation is to "SLAM" it as you would a chlorine pool, just trying to target the right PPM for bromine. Will using an algaecide (i.e. EasyCare Algatec) be okay/safe/helpful?

I've also read, though I forget the exact chemical/compound, that like CYA in a chlorine pool, bromine pools can accumulate some sort of stabilizer that also reduces effectiveness of bromine over time. How does one test for that or make that determination to empty a bromine pool?

 

[JoyfulNoise]

DMH - Dimethylhydantoin

It’s not quite as bad as CYA as it takes very high levels (some estimates are 300ppm or more) before it overstabilizes the bromine but it will do it eventually. Unfortunately there’s no way to test for it so you’re stuck either manually tracking bromine tablet use or just changing the water regularly.

 

[QPSUtah]

DMH - Dimethylhydantoin

It’s not quite as bad as CYA as it takes very high levels (some estimates are 300ppm or more) before it overstabilizes the bromine but it will do it eventually. Unfortunately there’s no way to test for it so you’re stuck either manually tracking bromine tablet use or just changing the water regularly.

Thank you. One other bromine related question - so I understand chlorine or other shock reactivates bromide into bromine. But when dealing with liquid chlorine specifically, and SLAM, I.e targeting 20 ppm bromine, can you essentially calculate chlorine required via pool math or Orenda app and that gives you the correct bromine? Specifically, I have a 5000 gallon therapy pool I’m treating, current bromine is 0, and I want 20 ppm bromine. Calculating for 10 ppm desired chlorine level requires 2 gallons chlorine. Does that 2 gallons then effectively give me 20 ppm bromine once reacted with bromide? Or is it just trial and error. Add some chlorine, test, add more chlorine, test again, until I get to 20?

I just came from the pool and added 2 gallons of chlorine. It seemed to give me 20 ppm bromine, more or less.

 

[JoyfulNoise]

Br (ppm) = 2.25 x FC

If you don’t know how much DMH is in the water, then you’re flying blind just like not knowing the CYA level in a chlorine pool. You can add enough LC to get you to a shock level of bromine but it may not help if the DMH is off the charts. So you’ll have to try to bring the water back to life and if it doesn’t seem to be working, then you’ll have to consider a drain and refill.

 

[QPSUtah]

Br (ppm) = 2.25 x FC

If you don’t know how much DMH is in the water, then you’re flying blind just like not knowing the CYA level in a chlorine pool. You can add enough LC to get you to a shock level of bromine but it may not help if the DMH is off the charts. So you’ll have to try to bring the water back to life and if it doesn’t seem to be working, then you’ll have to consider a drain and refill.

Awesome. Thank you so much. So if I want to target a delta of 20 ppm bromine, I’d calculate how much chlorine is needed to add ~9 ppm chlorine.

It’s a small pool, 5000 gallons, and they filled it about 18 months ago and are using the bromo bright tablets. I suspect it regularly goes stretches without tablets in their feeder. But I’ll give this a go and see what happens over the next couple of days.

Thanks again!

 

[Mdragger88]

Matt has you covered! Just wanted to answer about the Algaecide.
Algaecides are a preventative at best. They won’t do much for an active algae problem.
The only Algaecide we recommend is polyquat 60 and thats as a preventative during winter closing and some stain treatments that require a short period of low sanitizer levels.
Some others contain terrible things like copper or ammonia. So stick with the
SLAM Process & if you don’t make headway prepare to exchange some water to help aid you in your battle.

 

[QPSUtah]

As an update, green color has dissipated. So SLAM worked over a period of about 48 hours.