How low is too low for TA?

[somaholiday]

For my water gurus...

How low is too low for T/A?

I'm running 70-90 for a 200,000 G pool

 

[waste]

Give us all the chem #s and we'll give you a definative answer :-D

 

[JasonLion]

70-90 is what I usually recommend when you are not using dichlor or trichlor for chlorine. If your CYA levels are reasonably low you can often go lower, some people go down to 50 or so. Adding borates to 30-50 ppm allows you to lower TA even further. What level is appropriate for your pool depends on what you are using for chlorine, what the surface of the pool is made of (plaster, vinyl, etc) and where your other levels are.

 

[somaholiday]

cool, cool

I'm using sodium hypo with plaster.

FC 3
CC .5
PH 7.4
Alk 80-90
Cal 400-430
CYA 0
Temp 82
CSI 0 - .3

 

[JasonLion]

I take it this pool is indoors and has a heavy bather load. It is always a good idea to put some basic specs about your pool in your signature. That way we always have some context when answering a question.

Your numbers look good assuming you have lots of people using the pool. The FC level is a little too high if you don't have lots of people using the pool. Chem Geek is recommending adding just a little CYA to indoor pools to avoid the problems high chlorine levels can cause for hair, bathing suits, and the occasional "chlorine" allergy, but that is a very new idea at this point and not always accepted by health agencies.

Your TA and CH levels look fine. You could lower TA just a hair, but it really won't make any difference at this point.