Is there any way to test chlorine concentration at home?

[dborn]

Is there any way to test chlorine concentration at home?

Lately I thought I had a Stenner pump malfunction when my pool chlorine concentration dropped dramatically. After several tests, I have to conclude that my pump is fine and it's the chlorine in the holding tank, stored in my pool cabana that has been depleted.

It gets pretty hot in there (100F on hot sunny days), I'm in the process of insulating the pool cabana but had to stop due to a neck injury. I hope that insulation will help in preventing the afternoon heat build-up...

Am I correct in thinking that the depleted chlorine will have a tendency to "float" above newly added chlorine in the tank so that the pump, who draws the liquid from the bottom, is always using the fresher chlorine first and if I let the level drop a bit (not to the point of running out though), that I may end up using the 5% chlorine and that's when I think my pump is failing to add chlorine in the pool?

I'm currently using a timer to drive the Stenner pump but I plan to add an ORP sensor connected to a computer (a file server in the basement) to drive the pump so that it will automatically use more chlorine if needed.

Daniel

 

[JasonLion]

The best approach is to add some to the pool at night, measuring the FC level before and after. That isn't all that precise, but then none of the more complex approaches are all that precise either. Taylor makes a test kit designed to measure bleach concentration directly, but it is expensive and very error prone. Concentration can also be measured use dilution, but it takes lab grade equipment and procedures to do any better than simply adding it to the pool and seeing what happens.

 

[Patrick_B]

For what it is worth, I have a few thoughts I hope will help. There is another Kit, less error prone, and made by Chemetrics. Fool proof, pretty accurate, and expensive. the kit is about 60 USD and 0.80 per test. You'll be better off learning how much bleach to keep in your tank and for how long before it goes bad.

On ORP, you can take or leave this, but before you rely on it that heavily and link it down to your PC, and all that stuff please remember I told you.... ORP can be, and often is extremely unreliable as a means of control to maintain FC levels. Instruments and probes vary widely in terms of accuracy, often by wildly different amounts. People are going to agree, and disagree with me on this, but I feel compelled to warn you it's not all it's cracked up to be.