Try not to use any feeder fish to cycle as chances that the bio load they produce is still to small to grow a BB colony sufficient to support our monsterfishes. After u cycle with the small fishes and you put in you monsterfishes, the BB colony still would not be able to support the enormous waste that your monsterfish produces. Chances that there would be the usual spikes even after u so called cycled your tank with the small fishes. I prefer to use market prawn and dumps it in to the tank without anyfish and then put liquid BB inside the filter to kick start the whole bacteria colony. I then introduce more mp accordingly when the old ones rot away. Like this you would get a clean and clear tank when u place your beloved monsterfish in.