if i can ask do you have one of those odd styrofoam paneled ceilings? or possibly the snow flake spackle stuff? it looks like someone ran a broom on the ceiling of my textured ceiling right above the tank. are the shrimp live? i know if they breed in the tank you will get a buildup of the shells and stuff kind of like breeding brine people run brine breeders with 2 liters and a light bulb and an air stone. the shell floats to the top and the brine swim towards the bottom where the light is. possible the food did the dirty in ur tank and popped out some eggs?

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If its not broke dont fix it!!! If its broke save yourself the time and buy a new one!!!