I need some help, I currently have a 75 gal with electric yellow, rusty's, hap morri, red empress, german red peacock, flameback, and electric blue alhi. I noticed lately since I moved them from a 55 gal gravel based tank to my 75 gal sand based tank that they are hitting the sand on their side more often. I check my water and everything looks to be ok, except my nitrates were about 40ppm so I did a water change as well. Now I noticed some of the demonstrating breeding bechavior as well and one of my female electric yellows is holding. Is this behavior normal?