how to bbb

[chem geek]

I assume the pucks you are using are Trichlor in which case the chlorine that results from the Trichlor pucks is identical to the chlorine you add with bleach. The problem is that Trichlor adds more than just chlorine. It also adds Cyanuric Acid (aka CYA or conditioner or stabilizer) and it is the buildup of this CYA that is a problem because it combines with chlorine to make the chlorine less effective. This combining with chlorine also protects it (mostly) from degradation from sunlight so that is why it is good to have some CYA in outdoor pools exposed to sun. However, constant use of pucks builds up the CYA to unacceptable amounts.

After you get a good test kit (such as the Taylor K-2006) you will be able to measure your CYA and then can determine the proper level of chlorine you will need for proper disinfection and to prevent algae. If your CYA is way too high, then it will need to get lowered, but start with getting a full set of measurements from the test kit and then go from there (report your results here and we can help you figure out the next steps).

It is quite possible to have a pool with high CYA or low chlorine and not get algae since algae needs certain food sources to grow (nitrates and phosphates, for example), but it is generally not a risk worth taking. It is much easier to prevent algae through the proper maintenance of chlorine levels than it is to get rid of it.

Richard