sinking carnivore is best option, get off bloodworms asap, if it doesnt feed starve it a while, pellets are best, dont feed live feeders atm, 5cm thats tiny. I have 2, got them at 10cm, had them for about 2-3 weeks, 1 at my place, 1 at henwards, experiementing, my one at his place was with more filtration and a slightly different diet and has grown an inch within 3-4 weeks, both on pellets.