I have 12 half dollar to silver dollar body size Koi Angels in my 90 gallon tank(pic is in my avatar). Have had them for 6 months now. No sign of any breeding going on. No pairing either. I have a Fluval FX5 and 2 Aqua Clear 110s filtering it. Temperature is at 82 and I do 2 50% water changes each week. PH around 7.4. I feed them Kens Angelfish flakes,freeze dried brine shrimp and occasionally some frozen brine shrimp and bloodworms.Any suggestions on triggering these guys to spawn(other than listening to some Barry White music)?