Who Gives A Fish Forums

I'm setting up a breeding tank for my Discus and wondering about the ideal water depth. I've heard conflicting advice, some say shallow is better, others recommend deeper. My tank is 40 gallons, 18 inches tall, with a sponge filter and sand substrate. Water params are stable, 0 ammonia, 0 nitrite, nitrate under 10 ppm. Temp is 86°F. Anyone have experience with this?

I've bred Discus in a 20-gallon tank with 12 inches of water depth. It worked fine, but I noticed they seemed more comfortable when I increased it to 15 inches. They laid eggs on a vertical slate, so depth might not matter as much as surface area. What's your tank's footprint?

From what I've seen, Discus prefer deeper water for breeding, around 16–18 inches. It gives them more room to display and reduces stress. My pair spawned in a 55-gallon with 18 inches depth, heater set to 84°F, and they've been consistent. How old are your fish?

Yo, shallow tanks are sketchy for breeding. I'd go at least 16 inches deep, no cap. My Discus freaked out in a 12-inch tank, but chilled when I moved 'em to a deeper one. Got a 75-gallon now, 20 inches deep, and they're spawning like crazy.

Thanks for the input, everyone. My tank's footprint is 36x12 inches, and the fish are around 2 years old. I'll try adjusting the water level to 16 inches and see how they respond.

Water depth is crucial for Discus breeding, but it's not the only factor. Your tank's dimensions sound adequate, but ensure the water is soft and acidic, around pH 6.5. I use RO water with a bit of tap to stabilize. How often are you doing water changes?

I keep my breeding tank at 18 inches deep, 30 gallons, with a canister filter. The Discus seem to like it, but I've only had one successful spawn so far. Temp is 85°F, and I feed them beef heart twice a day.

Ain't no way I'd go shallow, bro. My Discus bred best in a 50-gallon, 20 inches deep. They need space to vibe. I got a pair of Eheim heaters, keeps the temp steady at 86°F. Sand substrate, no plants, just a few cones.

I've heard mixed things too, but my Discus spawned in a 15-inch deep tank. It's a 29-gallon, with a HOB filter and driftwood. Water changes every other day, 25%. They're picky, but it worked once. Maybe I got lucky?

TankWarrior wrote: ↑Tue Jul 01, 2025 10:52 am Yo, shallow tanks are sketchy for breeding. I'd go at least 16 inches deep, no cap. My Discus freaked out in a 12-inch tank, but chilled when I moved 'em to a deeper one. Got a 75-gallon now, 20 inches deep, and they're spawning like crazy.

I agree with TankWarrior. Depth reduces stress, and stressed Discus won't breed. My pair took months to spawn until I deepened the tank.