Spa chemicals accidentally added to pool

[Sjtripol]

I’m hoping you can help. My father works at a factory that produces pool and spa chemicals, and he gave me a large supply to get my pool up and running. We just bought our home, and this is our first summer having a pool.

I’ve been having a hard time keeping chlorine in the pool, so I decided to switch to the BBB method as described on this page. While searching for 10% bleach, I stumbled across a spa chemical, and the active ingredient in that is the same thing in the big blue bucket of pucks my dad gave me. 1-bromo 3-chloro 5.5 dimethylhydantoin.

I’ve been adding these to my inline chlorinator, but they haven’t seemed to do anything for my chlorine levels, so I’ve also been using bleach daily.

Here are are my concerns:
1. Did I just inadvertently convert my pool to a bromine pool?
2. Is there any risk to my equipment or to swimmers?
3. If I stop using these tablets and just use bleach going forward, will I be OK? (I’ve read that adding bleach reactivates the bromine, which sounds like a good thing.)
4. Since these are free, should I just keep using them this summer?
5. We have debated switching to a SWG. If we wanted to do that, is there a problem because I’ve used these chemicals?

My pool is crystal clear, and my test results from about 5 minutes ago are as follows:

TA 80
pH 7.5
TC 1
FC 1
CYA 60

 

[YippeeSkippy]

Sjtripol, welcome to TFP, where we rock our pools with science based pool care- the TFPC way!

I am afraid you have converted your water to a bromine pool. The problem with this is bromine is first off, *very* hard to test for, and each time you add chlorine you're just revving up that bromine again.

I can't advise you on safety but this thread my help you- How can I test Bromine levels?

Can you please make a signature line out to include information about your pool and equipment, and specify that it is a bromine pool. Thanks

Maddie

 

[Sjtripol]

Thanks for your reply, Maddie!

I don't want to continue to use this chemical, because I don't know for how long I can get it for free. I have a fiberglass pool, and I've read about the dangers of draining it. Here are some ideas I've had to try and address this:

1. Stop using the bromine tablets. Continue to use the BBB method until the sun/splash out/dilution/etc slowly eliminates the bromine chemicals in the pool.
OR
2. Stop using the bromine tablets. Drain the pool half way, refill, use BBB method for a couple weeks, then repeat the process.

Would either of these plans work? Also--how would I know I've removed the bromine? It appears that the test for chlorine and bromine is the same?

 

[mknauss]

You can exchange some water without draining.

If you place a low volume sub pump in the deep end and pull water from there while adding water in the shallow end you can do a fairly efficient exchange. That is assuming the water you are filling with is the same temperature or warmer than your pool water. If your fill water is much cooler than your pool water, then switch it. Add the water to the deep end (hose on bottom) and pull water from the top step.

The location of the pump and fill hose may change if you have salt water, high calcium, etc.
In my pool, with saltwater and high calcium when I drain, I put the pump in the deep end and hose in shallow end. The water in the pool weighs more per unit volume than the fill water from the hose.

Be sure to balance the water out and water in so the pool level stays the same.

 

[Sjtripol]

That's a good idea for the water exchange process. It should help me take less time with the overall process. Thanks for the tip.