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How often do you guys do water changes? I've got a 20 gallon with 6 Neon Tetras and a Betta. Right now I'm doing 25% weekly, but my Nitrates are still creeping up. Wondering if I should bump it to twice a week.

Twice a week might be overkill unless your tank's super stocked. What's your feeding routine like? Overfeeding can spike Nitrates faster than anything. Maybe cut back a bit and see if that helps before going full water change mode.

I do 30% weekly on my 30 gallon with similar stock. Nitrates stay around 20 ppm. If yours are higher, try adding more plants. Floating plants like Frogbit or Water Sprite suck up Nitrates like crazy. Also, check your tap water, sometimes it's got Nitrates already.

yo i do like 10% every 2 weeks but my tank's got mad plants n shrimp. if ur nitrates high maybe ur filter needs a clean? or ur substrate's dirty. just a thought.

starlet9 wrote: ↑Mon Jun 30, 2025 10:33 am yo i do like 10% every 2 weeks but my tank's got mad plants n shrimp. if ur nitrates high maybe ur filter needs a clean? or ur substrate's dirty. just a thought.

Cleaning the filter could help, but be careful not to overdo it. You don't want to crash your cycle. Maybe rinse the media in tank water during your next change.

I'd stick with weekly changes but increase the volume to 30-40%. More efficient than doing two smaller changes. Also, how old is your substrate? If it's over a year, it might be leaching nutrients back into the water.

My rule of thumb is 25% weekly for lightly stocked tanks, 50% for heavy stock. If Nitrates are still high, test your tap water. Some municipal supplies have Nitrates out of the tap, which makes it harder to keep levels down.

I agree with southbreeze. Increasing the volume might be better than frequency. Also, are you vacuuming the substrate during changes? Detritus buildup can contribute to Nitrates.

Man, I'm lazy with water changes, but my tank's got a ton of plants. Nitrates never go above 10. Maybe add some fast growers like Hornwort? That stuff's a nitrate hog.

nimbler wrote: ↑Mon Jun 30, 2025 1:32 pm Man, I'm lazy with water changes, but my tank's got a ton of plants. Nitrates never go above 10. Maybe add some fast growers like Hornwort? That stuff's a nitrate hog.

Hornwort's great, but it can get messy when it sheds. I'd recommend Anacharis instead. Grows fast but doesn't drop needles everywhere.