The sand filter pressure has never risen more than 1/2 psi. If by evidence of baqua products you mean the water changing colors no. The water did turn green the first few days be quickly cleared and has been that way since. What we do have is globs of dark "algae" (guessing that what it is) spots that appear on the bottom of the pool. We have been vacuuming them up and they are decreasing. Started out taking time off and testing every hour until reagents became an issue. We have had 50+ mile an hour winds that blew so much dust you could not see along with blowing so much tree debris into the pool it clogged the filter. And we have had lots and lots and lots of rain. Probably have replaced over 50% of the water including what was hauled in to open the pool. Currently have been testing 6 AM, noon, 4 PM, plus twice after sundown. Today we had rain and clouds with no sun and still when from 14.5 (noon test) to 8.5. There are a few globs which we will vac out tomorrow (hopefully no rain). I was reading another post in regard to the ladder. Our ladder has been in the pool this entire process. It is also one that is weighted with sand inside the unit. Could this be causing problems?