Who Gives A Fish Forums

Agree with checking the heater. Also, what's your lighting schedule? Too much light can stress 'em out, make 'em breathe heavy.

Flow's huge. If it's too strong, they'll ignore the cone entirely. Also, check your nitrates. Mine won't spawn if it's above 10ppm, even with perfect placement. Daily 20% changes help, and I dose a bit of tannin extract to soften things up.

Middle works if you've got enough space around it. Mine spawned fine with the cone centered, but they're picky about water flow. Keep the sponge filter on low, and make sure the cone's not directly under light. My pair freaked out when the LED was too bright overhead.

Keep the hose straight when you start. Kinks mess with the flow big time.

Re: 500 Gallon project, Dreaming of keeping Discus but afraid!

I really like the direction you're heading with the aquascape - plenty of open space for the Discus to roam, and some nice hiding spots to reduce stress. A couple of things caught my eye, though. Having set up a few large systems myself ...