Just picked up a delhezi n senegal as my first bichirs. My senegal has really washed out from his dark gray color. I am using pool filter sand as substrate what should i use to get his color back? Would mixing some black sand with the pfs help?
A darker substrate will help darken both your Polys colors, but more then likely he is just stressed from being purchased and getting used to new surroundings, he will darken in time
mostly due to stress, he may need some time to just hide in some places. Give it time and he'll come right back... but if you are really worried and need to get his color back... give him foods with additive coloring like carrotine. his natural colors should come back if its not due to stress.
A darker substrate will help darken both your Polys colors, but more then likely he is just stressed from being purchased and getting used to new surroundings, he will darken in time
Light.
I found my senegals went from solid light tan-yellow color with no tank lights, to the gray top-white bottom with 1 WPG lighting.
Your bichirs need a tan. Irradiate them.