Who Gives A Fish Forums

I just got a Clown Knife Fish and it's acting super sketchy. It's in a 125 gallon tank with a Fluval FX6, sand substrate, and some driftwood. Water params are good, 0 ammonia, 0 nitrite, 10 nitrate. Temp is 78F. It's not eating the Hikari carnivore pellets I dropped in. Any tips?

Clown Knife Fish can be picky eaters at first. Try live or frozen bloodworms to get it started. Mine took a week to adjust before it would touch pellets. Also, dim the lights, they're nocturnal and might be stressed by bright lighting.

What's the pH of your tank? These fish prefer slightly acidic water, around 6.5 to 7.0. If it's too high, that could explain the stress. Also, check for tankmates bothering it. They're shy and can get bullied easily.

ReelRiot wrote: ↑Mon Jun 02, 2025 7:14 am Clown Knife Fish can be picky eaters at first. Try live or frozen bloodworms to get it started. Mine took a week to adjust before it would touch pellets. Also, dim the lights, they're nocturnal and might be stressed by bright lighting.

Yep, totally agree. Mine was the same way. I used frozen brine shrimp at first, then slowly mixed in pellets. Now it's a pig for anything I drop in.

How's the flow in your tank? These guys like slow-moving water. If the FX6 is cranked up too high, it might be stressing it out. Try baffling the output or reducing the flow rate.

I'd also check for hiding spots. They need plenty of cover to feel safe. More driftwood or plants might help. Java fern or anubias are good since they don't need much light.

Thanks for the advice, everyone. I'll try the bloodworms and dim the lights. pH is 7.2, so I'll look into lowering it slightly. Tankmates are just some tetras, so no bullies there.

Mine took a while to settle in too. Just give it time. They're weird fish but once they chill, they're awesome.

What kind of sand are you using? Some substrates can mess with their barbels if it's too sharp.

matthew wrote: ↑Mon Jun 02, 2025 10:50 am What kind of sand are you using? Some substrates can mess with their barbels if it's too sharp.

Good point. Pool filter sand or CaribSea Super Naturals are safe bets. Avoid anything with sharp edges.