H. sf crossbar yala swamp

I have a colony from KMX that are now about one year old. I have a dominant male in full color, a sub-dominate male which had fin coloring but pale and four females. I have three questions...
1. Sometimes a female or two are lemon yellow???
2. Sometimes recently, a female is very very dark, almost black???
3. I have placed my spray bar shooting the length of the tank, should I point it down to give more flow at the bottom thus moving junk towards the intake but giving the bottom of the tank more water flow or point it upwards giving the bottom a calmer effect?

Thanks,
Leo

I'm not sure but I think pointing up for calmer bottom action would be better. Most fish breed on the bottom.