Who Gives A Fish Forums

Noticed my Discus are always hiding in the shadows of my 75-gallon tank. Water params are good, 0 ammonia, 0 nitrite, 10 nitrate. Temp is steady at 84°F with a Fluval heater. They're about 4 inches, fed twice daily with beef heart and flakes. Tankmates are 10 cardinal tetras and 6 corydoras. Lighting is moderate, 8 hours a day. Any ideas why they're so shy?

Could be the lighting. Discus often feel exposed under bright lights. Try dimming it or adding more floating plants like frogbit. Also, check if the tetras are bothering them. Even peaceful fish can stress Discus if they're too active.

Yep, lighting's prolly the culprit. Mine did the same till I swapped to a dimmer LED. Also, how's your tank layout? They need spots to retreat, like driftwood or tall plants. My crew chills behind a big piece of mopani wood most of the day.

mole wrote: ↑Mon Sep 01, 2025 11:47 am Yep, lighting's prolly the culprit. Mine did the same till I swapped to a dimmer LED. Also, how's your tank layout? They need spots to retreat, like driftwood or tall plants. My crew chills behind a big piece of mopani wood most of the day.

Agreed. Driftwood and plants are key. I'd also suggest reducing water flow if your filter's too strong. Discus prefer calm water, and high flow can make them hide more.

How long have they been in the tank? New Discus often hide for a week or two while adjusting. If it's recent, give 'em time. If not, check for bullying or illness. Are they eating normally?

Thanks for the suggestions. They've been in the tank for about 3 weeks. Eating fine, just skittish. I'll try dimming the lights and adding more plants. Appreciate the help!

Mine were the same till I added a black background. Sounds weird, but it made 'em feel safer. Also, how often are you doing water changes? Stable params are crucial for Discus confidence.

Could be the tankmates. Cardinals are chill, but sometimes Corys get too busy. Try observing if the Corys are nudging them. If so, might need to rearrange the tank or rehome a few.

Ever considered a tannin boost? I throw in some almond leaves, and my Discus love the darker water. Plus, it's got antibacterial benefits. Win-win.

SlyFox wrote: ↑Mon Sep 01, 2025 3:32 pm Ever considered a tannin boost? I throw in some almond leaves, and my Discus love the darker water. Plus, it's got antibacterial benefits. Win-win.

Tannins are great, but go slow. Too much can drop your pH fast. Start with one leaf per 20 gallons and monitor.