I have 4x80w T5's(2x12k and 2 actinic geissemann's) as well as 2x150w Mh's,14k. Tank size is 1800x600x500. I feed my nennie's once a week,give them mussel and a squirt of red plankton.Not so long ago my other bta made a split,now the smalles,when open,is about fist size.