is my co2 level safe for fish?

[Raptor]

I've been running CO2 in my 20 gallon planted tank for about a month now. My drop checker is lime green, but my fish seem a bit sluggish. Is 30 ppm too high for them? I've got Neon Tetras, a Betta, and some Cherry Shrimp in there.

[willy]

30 ppm is usually fine, but Bettas can be sensitive. What's your pH and KH? If those are outta whack, it could mess with how the CO2 affects the fish. Also, how long are you running the CO2 each day?

[kalemo]

I agree with willy. My Betta didn't like high CO2 either. Maybe cut it back to 20 ppm and see if they perk up. Shrimp are usually chill with it, but Tetras can be sketchy.