Rescued guppy with fin nips and lethargic corys

[Eonixar]

I'd also look at the filter flow. Too strong and it might stress them out. Corys like calm water.

[blueoceans]

Oh no, poor little guys! I'd definitely add some stress coat and maybe a bit of aquarium salt. Just a teaspoon per gallon to help with the fin healing. And yeah, check the oxygen!

Be careful with salt if you've got live plants though. Some species don't handle it well.

[zenox8]

True, salt can be rough on plants. If you're gonna use it, maybe do a half dose and monitor. Also, what's your lighting schedule? Too much light can stress fish out.

[Wildman]

Good point on the light. I run mine for 8 hours max. Also, make sure you're not overfeeding. Leftover food can mess with the water quality big time.

[bronzo]

Thanks for the tips, everyone. I'll check the oxygen and add some almond leaves. Substrate is sand, so that shouldn't be the issue. Gonna keep an eye on the guppy's behavior.

Sand is good for corys. Maybe try feeding them some sinking pellets with garlic to boost their immune system.

[prince]

Garlic is a solid move. Also, if the guppy's fins don't start healing in a few days, might wanna isolate it to prevent further nips.

[bertha]

Yeah, isolation could help. Just a little breeder box in the same tank so it's not too stressed. And yeah, go easy on the salt if you've got plants.

[Globe]

Have you tested for nitrates recently? Even if they're low, a sudden spike could cause issues.

[blueoceans]

Nitrates at 10 are fine, but yeah, keep an eye on them. Also, how's the guppy's color? Pale could mean stress or illness.

[Freshstar]

Guppy's color looks okay, just the fins are rough. I'll try the garlic pellets and keep monitoring. Thanks again, everyone.