Darn it! Not one of my fish ate the 10mm sinking pellets even after fasting for two days. Swallowed and spit out...... These pellets are extremely dense/hard which none of my fish like. The consistency is also not uniform from pellet to pellet.....if you soak 10 pellets in water, then crush with your fingers, some pellets will be soft while others are still extremely hard....not necessarily a bad thing, just thought it was worth mentioning. Back to massivore for the time being.......