i got 2 jack dempsys in a tank, ones about 7'' the other is 4''i thought i had 2 males, but im starting to think otherwise the bigger one would normally chase the smaller all around the tank and the smaller would hide in a treasure chest only he would fit in. but recently they have been getting along very well. the other day i began to see them digging out a cave together. they've been doing it for the past few days now.
i know the bigger is a male for sure. his top fin is very long and pointed, and hes very colorful. the smaller is more blackish, with less blueish green spots. his top fin is pointed, but not as long. in my past experience with jd pairs, the females top fins were almost completely rounded off.
my last pair of dempsys did spawn, but the babies never lived. i did have other fish and a blue lobster in the tank which ate them. i tried separating the depseys and babies from the other fish by using a plexi glass board. every morning id find the lobster on the other side. i have the tall plastic grass u place at the bottom to protect the babies from other fish, but it dont work against lobsters.
the depmseys are the only fish in the tank, i think ill have better results this time.