Who Gives A Fish Forums

How often do you guys change water in your Discus tanks? I've got a 75 gallon with 6 adults, running a Fluval FX6, and I'm doing 50% changes twice a week. They seem happy, but I'm wondering if I can cut it back to once a week without stressing them. Temp's at 86F, pH 6.8, TDS around 150. Feed them beef heart mix twice a day, frozen bloodworms as treats.

I'd stick with twice a week if you're feeding that heavily. Discus are messy, and beef heart fouls the water fast. My 90 gallon has 8 adults, and I do 50% changes every 3 days. Same setup as you, FX6, but I also run a sponge filter for extra bio. TDS creeps up past 200 if I slack, and they start getting sketchy vibes.

Rusty wrote: ↑Fri Jul 18, 2025 10:03 pm I'd stick with twice a week if you're feeding that heavily. Discus are messy, and beef heart fouls the water fast. My 90 gallon has 8 adults, and I do 50% changes every 3 days. Same setup as you, FX6, but I also run a sponge filter for extra bio. TDS creeps up past 200 if I slack, and they start getting sketchy vibes.

Yep, agree with Rusty. I do 40% changes twice a week on my 55 gallon, 5 Discus, Eheim 2217. If I skip a change, nitrates hit 20ppm by day 5. They're chill with it, but I notice less appetite if I push it. Sand substrate, driftwood, no plants.

Mine are juveniles in a 40 breeder, so I'm doing 30% daily. Once they hit 4 inches, I'll switch to every other day. Temp's at 84F, pH 7.0, TDS 120. Using RO mixed with tap, Seachem Prime. They're growing fast, but I'm paranoid about stunting. Filter's an AquaClear 110, bare bottom for now. How old are yours, gett246?

Ayy, I'm lazy with my 65 gallon, so I do one big 70% change weekly. 4 Discus, canister filter, lots of plants. They're fine, but I feed lighter, mostly pellets and flakes. Beef heart's a weekend treat. Nitrates stay under 10ppm, but my tank's heavily planted with CO2. If you're gonna cut back, maybe try 60% once a week and test nitrates daily for a bit.

I tried cutting back to once a week and my Discus got all grumpy. Back to twice a week, 50%, and they're cool again. 55 gallon, 4 fish, HOB filter. Temp 85F, pH 6.5. They're picky little divas, man. Also, my tap water's kinda hard, so I use RO mix. Forgot to mention that earlier.

Frequency depends on stocking and feeding. My 75 gallon has 5 Discus, FX4, and I do 30% every 4 days. Feed them once a day, mix of pellets and frozen. Nitrates stay around 15ppm. Sand substrate, some driftwood. They're not growing as fast as jade's, but they're healthy. Maybe your adults can handle less changes if you tweak feeding.

Thanks for the input, everyone. I'll test nitrates more often and maybe tweak the feeding schedule before cutting back on changes. Mine are around 2 years old, jade. Appreciate the help!

gett246 wrote: ↑Sat Jul 19, 2025 3:49 am Thanks for the input, everyone. I'll test nitrates more often and maybe tweak the feeding schedule before cutting back on changes. Mine are around 2 years old, jade. Appreciate the help!

Smart move. Also, watch their behavior after changes. If they're darting or clamping fins, the new water might need adjusting. I age mine for 24 hours with airstones, same temp as the tank. Helps avoid shock.

Aging water's a pro tip. I just use a Python and temp-match on the fly, but my tap's pretty stable. If yours is sketchy, Rusty's method's gold. Also, if you're gonna cut back, maybe add some floating plants to help with nitrates. Water lettuce works great, just don't let it take over.