Well i can say from experience, it will not pop from touching it. I did it last night just to mess with him, he bit me so i messed with him

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As for feeding: Hicari gold(flaoting) 1-2 times a day, about 5 large pellets
Omega one cichlid pallets(floating) 1-2 times a day about 10 med pellets
night crawler worms 3 times a week( about 1 1/2 each time)
The only other things i can think of to assume why he's doing so good are:
genetics, although his father had no kok what so ever.
water quality, i do a 50-75% weekly water change
water volume, 125 gallons
and lastly the fact that he has a lot of enrichment oppertunity's, female zz who's larger than him, pleco's and larger marbles.
Other then that I guess i just got lucky.
Thanks to everyone for the comments