i just recently purchased 2 1.5in senegals. I have them in a 10g grow out. Can i keep them in there until about 6 or 7 in to put in my 125? I know its pushing it.
I think a 20 long would be more suitable. Ideally, you want to feed varied, high quality foods and stay on top of water quality. If you really want them to grow fast, I would perform a large, daily water change. Even still, it took me over a year for my senegals to pass the 7" mark