Who Gives A Fish Forums

Need a solid hang-on filter for my 55-gallon Discus tank. Currently running a cheapo one but it's not cutting it. What's the best option for these sensitive fish? Tank's got sand substrate, driftwood, and a few live plants. Water's at 84°F, pH 6.5, and I do 30% water changes twice a week. Fish are about 4 inches, been with me for 6 months.

For Discus, you want gentle flow but strong filtration. The Seachem Tidal series is great, especially the Tidal 55. It's got a huge media basket, adjustable flow, and self-primes. I've used it in my 75-gallon with Discus for a year, zero issues. Keep up with those water changes though, they're key.

I've got a Fluval C4 in my 40-gallon. It's quiet and does the job, but I'm not sure if it's strong enough for a 55. My Discus seem happy, but they're smaller, around 3 inches. Maybe someone else can chime in?

Olive wrote: ↑Tue Jul 08, 2025 11:33 am For Discus, you want gentle flow but strong filtration. The Seachem Tidal series is great, especially the Tidal 55. It's got a huge media basket, adjustable flow, and self-primes. I've used it in my 75-gallon with Discus for a year, zero issues. Keep up with those water changes though, they're key.

Yep, the Tidal's a beast. I run the Tidal 75 in my 60-gallon, and it's perfect. Adjustable flow is clutch for Discus, they hate strong currents. Also, the surface skimmer keeps the water crystal clear.

I've been using an AquaClear 70 for my 55-gallon Discus tank. It's reliable, but the flow's a bit strong even on the lowest setting. I had to baffle it with a sponge. Works fine now, but if I had to do it over, I'd go with the Tidal like Olive suggested.

My uncle swears by the Marineland Penguin. He's got a 50-gallon with Discus and says it's quiet and easy to clean. I don't have personal experience though, just passing it along.

Thanks for the recs, everyone. Gonna check out the Tidal 55. Sounds like it's the move. Appreciate the help!

Roadman wrote: ↑Tue Jul 08, 2025 4:50 pm Thanks for the recs, everyone. Gonna check out the Tidal 55. Sounds like it's the move. Appreciate the help!

No problem. Just a heads up, make sure to rinse the media in tank water during water changes. Keeps the biofilter intact. Also, toss in some Purigen if you want extra polish.

Purigen's a game-changer. I run it in my Tidal, and my water's never been clearer. Just remember to recharge it with bleach and Prime every few months.

I've never tried Purigen. Might have to grab some. Does it mess with the pH at all?