i have just recently placed about 1.5 inches of silica sand in bottom of tank before i had crushed coral what i need to know is why with this sand just being introdc'd i have red algea growing on top. i run a mag 350 a whisper 2 for filter no undergravel,lighting consists of 20 watt actinic 20 watt daylight and an aqua glo 20 watt 18000k,all water parameters are grav1.023 dkh 12 temp 79 deg nitrates at 0 also use phosphate pads and ammonia pads,is it the sand just cycling? any insight would be much appreciated. i also use reef plus every week .5 dose. sorry also have 65 lbs indonesian live rock 2 crabs 2 turbo snails gorgonians and exenia.