chlorine levels

[chem geek]

Cal-Hypo should usually be pre-dissolved in a bucket of pool water and then when added to the pool by pouring over a return flow with the pump running, any residue should be swept with a pool brush. You do not want to add concentrated chemicals quickly in one place since some of them can settle to the bottom and cause problems. You are fortunate you have a plaster pool because with a vinyl pool such settling of Cal-Hypo could have bleached the liner.

If this white powder is easily brushed away, then it's undissolved Cal-Hypo. If it doesn't dissolve with circulation, then it may be residue from the Cal-Hypo -- basically filler -- which is probably not harmful, but is annoying and yet another reason to use chlorinating liquid or bleach instead of Cal-Hypo, or at least to use another brand.

[fhorta]

so i heard (dissolve solids in water first before pouring in). and all this time i was trying to get rid of it as i poured 8lbs at a a time thinking it was something else...now i know. thanks.