well if you are willing to pay the price for snowflake clowns you should be willing to pay for the food, this hobby is expensive, very expensive and with three tanks, you may have dung yourself into a deep hole. you can just blend it up and freeze, that is one of the easiest ways, and if you do that you can add vitamins and other beneficial goodies for them into the mixture. the fish larvae, even though i may get thrashed for this, i just catch when i go fishing. whe the bite is slow, i just look around the docks and catch with a dipnet and even when im in the boat , i catch tiny sardines and glass minnows. i usually put them in aerated and filtered bucket in my room for a week with daily water changes to make sure they are clean, but im not too worried about them getting sick.