I figured the reason that it would drop and then level off was probably because of whatever was in the rock and sand. Would you recommend continuing the recommended dose only and daily? I assume as the levels drop in the tank the rock and sand would release some and therefore not really showing a drop on my test, but eventually I would see it begin to lower. Does this sound correct or should I increase the dose?It can be very hard to reduce phosphate because a lot may be bound to rock and sand. t may take a lot more for a lot longer than Brightwell understands.