bromine spa in SWG chlorine pool

[mmeyer]

This is my first year as a pool owner. I have an in ground pool 18k gallon and a 1k gallon in ground spa in Seattle. For inexplicable reason I was given a bromine swimmer and tabs for the spa to use over the winter (while I was told to use a chlorine swimmer in the pool). The spa and pool are connected through a waterfall feature. I would drain the spa into the pool about once a month.

Once summer arrived we added the salt and started the SWG chlorine system. Over weeks, I was not able to record a chlorine level (DPD testing kit). The water looked great, so I kept using the pool. I kept an eye on pH and TA and was adding muriatic acid faithfully. I noticed TA rising to 200ppm and combated that with muriatic acid and aeration. I was getting kind of nervous and our pool contractor suggested we replace the SWG cell.

After getting the TA back to 120ppm, the SWG seemingly worked again. I was finally able to get the free chlorine between 3 and 5!

Now I'm wondering if it wasn't the bromine tabs that were wasting my chlorine and after the summer sun and pool use the bromine was used up.

Obviously (and especially after reading much of what was posted here about bromine and chlorine) I won't be using the bromine tabs and swimmer again. Do I need to take a measurement of bromine or do anything else. All seems well with water clarity, comfort, pH, TA and chlorine levels.

 

[Lershac]

I think you may have had a nascent algae bloom or some other contaminants in the pool that were consuming your FC right off the bat, and it just took a while for the SWG to get on top of it.

If it ever happens again, I would raise FC to shock level using bleach (find your shock level here) and do an overnight Chlorine Loss test (learn how here) to see if anything was consuming it. I bet there was.

 

[chem geek]

Welcome to TFP!

It's also possible that with the high TA, that if the CH was moderate to high that you had scaling in the salt cell and that prevented it from producing full output.

 

[257WbyMag]

Welcome to TFP! Looks like you have gotten some good advice thus far.

 

[mmeyer]

Thank you for your posts and for running this website!

It sounds like no one is too concerned with the amount of bromine I dumped into my pool. It was probably less than 4 small pucks all winter and something I'm sure not to repeat!

I really like the thought of algae consuming the free chlorine. I remember having to brush off something slimy and slightly brown off the walls earlier in the summer. Maybe once I got that under control, I was finally getting decent levels in the pool. I also increased the pump run time. Always surprising that the pool contractors don't spend much time giving you a better run down on what to do. Maybe I should get around to reading the 100 page binder they gave me...

Next stop, inspecting and cleaning the SWG cell. If there are a lot of flakes on the surface, that might help prove that the TA was indeed too high!

Thanks for all your help!

 

[Lershac]

Well something I am learning in my build... The builder is very knowledgeable about the physical aspects of building the pool. Operating a pool? Not so much. Now I am certainly not knocking pool builders for being ignorant. Many ARE very knowledgeable about it. But some are not. Some just dont take the time to educate you.

But to throw in a car analogy.... its like expecting the guy who built your car over in dearborn michigan to know the ramifications of using synthetic oil over the use of petroleum distilled oil. Some of the guys will know, and some of em are just there for the paycheck.

 

[mmeyer]

No doubt true. They also need to balance the loss in sales if they point out just how complex and time consuming caring for a pool is. I actually enjoy the challenge and like to try understand what is going on in the pool, but I suspect many would just as well pay for the service and be done with it...