Who Gives A Fish Forums

Noticed my Discus hiding in the debris at the bottom of the tank today. Water params are good, 0 ammonia, 0 nitrite, nitrate around 10 ppm. Tank is 75 gallons, planted with driftwood, and they're usually out and about. Anyone else seen this behavior? They're about 6 months old, fed twice daily with frozen bloodworms and flakes.

Yo, that's sketchy. My Discus did the same thing when I had a power outage last winter. Temp dropped to 72°F and they were all over the substrate like it was a safety blanket. What's your heater situation? Also, any new tankmates recently? Sometimes they freak out if you add something rowdy.

dramatic wrote: ↑Fri Aug 01, 2025 11:38 pm Yo, that's sketchy. My Discus did the same thing when I had a power outage last winter. Temp dropped to 72°F and they were all over the substrate like it was a safety blanket. What's your heater situation? Also, any new tankmates recently? Sometimes they freak out if you add something rowdy.

Temperature is crucial. Discus prefer 82–86°F. If your heater's struggling, they'll stress. Check your thermometer accuracy too. I've seen cheap ones off by 3–4 degrees. Also, how's your water change routine? Debris buildup can spike organics.

Mine did this after I swapped their canister filter media too fast. Messed with the bio balance for a week. If you've changed anything recently, like filter flow or substrate cleaning, that could be it. They're sensitive to sudden changes. Maybe try a 20% water change and see if they perk up.

I'm new to Discus, but my LFS guy said they hide if the light's too bright. What kind of lighting you running? Mine are under LED at 50% and they're chill.

soup wrote: ↑Sat Aug 02, 2025 3:57 am I'm new to Discus, but my LFS guy said they hide if the light's too bright. What kind of lighting you running? Mine are under LED at 50% and they're chill.

Thanks for the tips, everyone. Lighting is Fluval Plant 3.0 at 70%. I'll dial it back and check the heater. No new fish, but I did clean the filter last week. Gonna do a water change tonight.

Filter cleaning could totally be the culprit. Those dudes hate when their bacteria buddies get disrupted. Next time, rinse the media in tank water, not tap. Chlorine's a killer. Also, throw in some StressGuard if you've got it. Helps 'em bounce back faster.

Agreed on the filter care. Another thought: how's your CO2 levels if it's a planted tank? Too much CO2 can make them lethargic. Test your pH before lights on and after to see if it's swinging. Stable is better than perfect with these fish.

vimster wrote: ↑Sat Aug 02, 2025 6:35 am Agreed on the filter care. Another thought: how's your CO2 levels if it's a planted tank? Too much CO2 can make them lethargic. Test your pH before lights on and after to see if it's swinging. Stable is better than perfect with these fish.

Yep, pH swings are brutal. Mine hid for days once because my CO2 solenoid stuck open overnight. Now I run a pH controller. Worth every penny if you're heavy into plants.

This is all super helpful. Gonna check my CO2 too. Didn't realize Discus were this finicky. Glad I joined this forum!