Handling high pH levels

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toothman
Posts: 3
Joined: Thu Oct 10, 2024 8:42 pm

Handling high pH levels

Post by toothman »

My tap water's pH is around 8.2, and my tank's sitting at 8.0. I've got a 20-gallon with a pair of Angelfish and some Java Fern. Anyone got tips to bring it down without messing with the fish too much?
fusioncore
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Joined: Thu Oct 10, 2024 7:01 pm

Re: Handling high pH levels

Post by fusioncore »

Yep, high pH can be a pain. I'd start with adding driftwood or almond leaves. They release tannins, which can lower pH naturally. Just gotta watch out for the water turning brown, but some folks dig the blackwater vibe.
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easton
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Joined: Thu Oct 10, 2024 2:09 am

Re: Handling high pH levels

Post by easton »

Driftwood's a good call. Also, what's your KH like? If it's high, pH won't budge much. You might need to dilute with RO water or use a buffering substrate like Fluval Stratum. Test your KH first though, no point guessing.
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bronzecat
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Joined: Thu Oct 10, 2024 2:26 am

Re: Handling high pH levels

Post by bronzecat »

I've had luck with peat moss in the filter. It's cheap and works slow, so less shock for the fish. Just toss a handful in a mesh bag and let it do its thing. Bonus, it gives the tank a kinda rustic look.
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softly
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Joined: Thu Oct 10, 2024 4:38 am

Re: Handling high pH levels

Post by softly »

fusioncore wrote: Fri Jun 27, 2025 7:52 pm Yep, high pH can be a pain. I'd start with adding driftwood or almond leaves. They release tannins, which can lower pH naturally. Just gotta watch out for the water turning brown, but some folks dig the blackwater vibe.
Tannins are great, but if you're not into the color, Seachem Acid Buffer works. Just dose carefully and monitor pH daily. Overdoing it can crash your tank.
filtercore
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Joined: Thu Oct 10, 2024 3:28 pm

Re: Handling high pH levels

Post by filtercore »

RO water's the safest bet long-term. Mix it with your tap to get the pH you want. I run a 50/50 mix in my 40-gallon, keeps things stable. Just remember to remineralize, pure RO's no good for fish.
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duskmist
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Joined: Wed Oct 09, 2024 10:03 pm

Re: Handling high pH levels

Post by duskmist »

Before you start tweaking, are your fish showing stress? Angels can adapt to higher pH if it's stable. Sudden changes are worse than a steady high pH. Test your tap and tank for consistency first.
Korvoa
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Joined: Thu Oct 10, 2024 7:48 pm

Re: Handling high pH levels

Post by Korvoa »

Man, I tried all this stuff and my pH just laughed at me. Ended up switching to a sand substrate and it magically dropped to 7.4. No idea why, but I'll take it. Tank's a 29-gallon with Corys and Tetras.
Riverwolf
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Joined: Fri Dec 16, 2022 12:19 pm

Re: Handling high pH levels

Post by Riverwolf »

Stability's key here. If your fish are healthy, maybe just leave it be. But if you're set on lowering pH, go slow. Fish can handle a lot if changes are gradual. You're doing great asking for advice first.
toothman
Posts: 3
Joined: Thu Oct 10, 2024 8:42 pm

Re: Handling high pH levels

Post by toothman »

Thanks for all the tips, folks. Gonna test my KH and maybe grab some driftwood. Appreciate the help!
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