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My discus breeding tank's water is looking a bit cloudy lately. I've got a 75-gallon tank with six adult discus, sand substrate, and a Fluval FX6 filter. Water params are good, 0 ammonia, 0 nitrite, nitrates around 10 ppm. I do 50% water changes twice a week, but the cloudiness won't cut it. Anyone else dealt with this?

Cloudy water in a discus tank can be a few things. First, check if it's a bacterial bloom. How old is the tank? If it's newer than 3 months, it might just need time to settle. Also, what's your feeding routine? Overfeeding can mess with clarity. I'd recommend cutting back on food for a couple days and see if it clears up.

mole wrote: ↑Thu Jul 24, 2025 12:03 pm Cloudy water in a discus tank can be a few things. First, check if it's a bacterial bloom. How old is the tank? If it's newer than 3 months, it might just need time to settle. Also, what's your feeding routine? Overfeeding can mess with clarity. I'd recommend cutting back on food for a couple days and see if it clears up.

Yep, I've had the same issue. Mine cleared up after I switched to a tighter feeding schedule. I feed frozen beef heart twice a day now, and the water's been crystal clear. Maybe try that?

I'd also check your filter media. If it's clogged or not cycled properly, that can cause cloudiness. What kind of media are you running in the FX6? I use a mix of sponges, bio rings, and filter floss, and my water's always pristine. Also, how's your flow? Discus don't like strong currents, but you still need enough to keep debris moving.

Thanks for the tips, everyone. The tank's about 4 months old, so maybe it's still settling. I'll try cutting back on food and check the filter media. I'm using the stock FX6 setup with sponges and bio media, but I'll add some filter floss and see if that helps.

Yo, cloudiness is a vibe killer for sure. I had the same prob in my 55-gallon. Turned out my substrate was the culprit. Sand can hold a ton of gunk if you ain't vacuuming it right. I started doing deeper gravel vacs during water changes, and boom, clear water in a week. Maybe give that a shot?

Another thing to consider is your water source. If you're using tap water, are you treating it with a conditioner? Chloramines can sometimes cause cloudiness. I use Seachem Prime and haven't had any issues. Also, what's your pH and hardness? Discus prefer softer water, and if it's too hard, that can stress them and mess with clarity.

I'm kinda new to discus, but my tank was cloudy too. I added some floating plants like frogbit, and they helped a ton. They soak up excess nutrients and give the fish some shade. Maybe try that? Also, how's your lighting? Too much light can cause algae blooms, which'll make the water look murky.

If all else fails, you might wanna try a UV sterilizer. I hooked one up to my canister filter, and it cleared my water in like 3 days. They're pricey, but worth it if you're serious about keeping discus. Just make sure you get one rated for your tank size.

Man, I feel your pain. My tank was a cloudy mess until I realized I was overfeeding. Now I stick to a strict schedule and use an auto feeder when I'm not home. Also, how often are you cleaning your filter? I rinse mine every 2 weeks, and it's made a huge difference.