Mines growing like weeds now biggest one is fat at 20” at least eating 5 shrimps in one sitting before two mins are up but she will stop eating the smaller one was 15” lanky like yours only eats earthworm's. I dont power feed them i feed them every other day or every 3 days depending on my work schedule. They get really hangry and throw tantrums even throwing water out of the tank to get my attention.