Who Gives A Fish Forums

I've been doing weekly 50% water changes on my 75-gallon Discus tank, but lately they've been acting skittish afterward. Water params are good, 0 ammonia, 0 nitrite, nitrate around 10 ppm. Temp stays at 84°F with a Fluval heater. Anyone else notice stress after changes? I use Seachem Prime, but maybe I'm missing something.

How's your pH stability? Discus are super sensitive to sudden shifts. If your tap pH is way different from the tank, even with Prime, it can freak them out. I drip acclimate new water over an hour to avoid this. Also, check your TDS, they might not like the mineral swing.

mole wrote: ↑Wed Sep 03, 2025 1:42 pm How's your pH stability? Discus are super sensitive to sudden shifts. If your tap pH is way different from the tank, even with Prime, it can freak them out. I drip acclimate new water over an hour to avoid this. Also, check your TDS, they might not like the mineral swing.

Solid advice. I'd add that temp matching matters too. Even a 2°F difference can stress them. I use a digital thermometer to match new water to the tank before adding. Also, how's your flow rate? High flow during changes can spook them.

Y'all making this way too complicated. Just toss a towel over the tank for an hour after changes. They'll chill out. Mine used to dart around like crazy, now they barely notice. Also, maybe your water change bucket's haunted. Ever think of that?

Nah, it's not ghosts, lol. But seriously, I had this issue till I started aging my water. Let it sit 24 hours with an airstone to off-gas chlorine and stabilize. My Discus stopped hiding after changes. Also, feed 'em right after, distracts them.

Hartan wrote: ↑Wed Sep 03, 2025 7:10 pm Nah, it's not ghosts, lol. But seriously, I had this issue till I started aging my water. Let it sit 24 hours with an airstone to off-gas chlorine and stabilize. My Discus stopped hiding after changes. Also, feed 'em right after, distracts them.

Aging helps, but not everyone's got space for that. Try smaller, more frequent changes—maybe 20% every 3 days. Less shock, same clean water. And yeah, feeding after is a pro move.

Thanks for the tips, everyone. Gonna try aging the water and smaller changes. Appreciate it!

Another thing: check your water pressure. If you're refilling too fast, it can stir up substrate or debris, stressing the fish. I use a slow siphon to refill, takes longer but keeps 'em calm.

I've had luck with adding Indian almond leaves during changes. The tannins seem to relax them. Plus, it makes the tank look kinda cool.

basis wrote: ↑Thu Sep 04, 2025 6:30 am I've had luck with adding Indian almond leaves during changes. The tannins seem to relax them. Plus, it makes the tank look kinda cool.

Tannins are great, but watch your pH if you're not buffering. Soft water + leaves can drop it fast. I use crushed coral in the filter to balance it out.