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My 75-gallon Discus tank keeps having ammonia spikes, even with weekly 50% water changes. I've got a Fluval FX6, sand substrate, and a bunch of Amazon swords. Tankmates are 6 Cardinals and 2 Rams. Feeding twice a day with frozen bloodworms and pellets. Any ideas why this keeps happening?

First, cut back on feeding. Bloodworms are messy, and overfeeding is a common cause. Try once a day, and see if the spikes stop. Also, check your filter media. If it's clogged, beneficial bacteria can't do their job. What's your nitrate level? High nitrates can hint at overstocking.

Your tank's overstocked. Discus need way more space, and those Rams aren't helping. You're gonna crash the cycle if you don't fix this fast.

Haterw wrote: ↑Mon Apr 28, 2025 6:18 pm Your tank's overstocked. Discus need way more space, and those Rams aren't helping. You're gonna crash the cycle if you don't fix this fast.

Not necessarily. I've kept Discus in a 75 with similar stock, but you gotta stay on top of maintenance. How old is your tank? New setups are more prone to spikes.

I agree with Deepsea about feeding. Also, have you tested your tap water? Sometimes there's ammonia in there straight from the source. A good conditioner like Seachem Prime can help neutralize it.

Yo, try adding some floating plants like frogbit. They suck up ammonia like crazy. And maybe chill with the bloodworms, they're sketchy for water quality. Pellets are way cleaner.

What's your water change routine? If you're only doing 50% weekly, try splitting it into two 25% changes. More frequent smaller changes can stabilize things better.

Thanks for the tips, everyone. I'll cut back on feeding and test my tap water. Tank's been running for about 8 months, so it's not new. Gonna try adding some frogbit too.

Slybird wrote: ↑Tue Apr 29, 2025 12:10 am Thanks for the tips, everyone. I'll cut back on feeding and test my tap water. Tank's been running for about 8 months, so it's not new. Gonna try adding some frogbit too.

Good call. Also, check your filter flow. If it's too low, debris can build up and cause spikes.

Another thing, how often do you clean the sand? Detritus can get trapped and rot, causing ammonia. A gentle stir during water changes can help.