The 2 mm seems not very intrested to market prawn..may be due to the breeder used to feed them blood worm. they will take 1 or two cuts..thats it.. and earthworm is very hard to find at the moment. will try feeder catfish.. want to pump up first and then wean to MP..mshuangchao;2114069; said:Market prawns are always a delicacy for rays, mine love them more than anything else.