best discus tank water testing

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Wind
Posts: 21
Joined: Wed Oct 23, 2024 5:25 pm

best discus tank water testing

Post by Wind »

What's the best way to test water for Discus? I've got a 75 gallon tank with 6 adults, sand substrate, and a Fluval FX4 filter. Been using API test strips but heard they're sketchy. Need something reliable, gonna do daily tests for a bit.
Olive
Posts: 25
Joined: Wed Jun 07, 2023 9:12 pm

Re: best discus tank water testing

Post by Olive »

API strips aren't precise enough for Discus. Get a liquid test kit like the Salifert or Red Sea Pro. Test ammonia, nitrite, nitrate, pH, and KH daily. Keep temp at 84°F, and do 30% water changes every other day with RO water mixed with a mineralizer.
Coralite
Posts: 29
Joined: Thu Oct 10, 2024 6:15 pm

Re: best discus tank water testing

Post by Coralite »

Olive wrote: Fri Aug 01, 2025 8:01 am API strips aren't precise enough for Discus. Get a liquid test kit like the Salifert or Red Sea Pro. Test ammonia, nitrite, nitrate, pH, and KH daily. Keep temp at 84°F, and do 30% water changes every other day with RO water mixed with a mineralizer.
Yep, liquid kits are the way to go. I use Seachem Prime for conditioning and a TDS meter to check purity. My Discus are way happier since I switched.
bigDiscus
Posts: 13
Joined: Sat Jun 08, 2024 7:32 pm

Re: best discus tank water testing

Post by bigDiscus »

If you're gonna test daily, cut it with the strips. Hanna Checkers are pricey but worth it for accuracy. I run a 125 gallon with 10 Discus, planted with CO2, and my pH swings were brutal till I got one.
Seadog
Posts: 19
Joined: Wed Aug 02, 2023 1:00 pm

Re: best discus tank water testing

Post by Seadog »

Stick to liquid tests for now. I've got a 55 gallon with 4 juveniles, sponge filter, and driftwood. Tested with strips for months and got false zeros. Switched to API Master Kit and found nitrates at 40 ppm. Scary stuff.
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keeper
Posts: 14
Joined: Wed Oct 09, 2024 11:44 pm

Re: best discus tank water testing

Post by keeper »

Seadog wrote: Fri Aug 01, 2025 11:31 am Stick to liquid tests for now. I've got a 55 gallon with 4 juveniles, sponge filter, and driftwood. Tested with strips for months and got false zeros. Switched to API Master Kit and found nitrates at 40 ppm. Scary stuff.
Same here. My tap water's KH is super low, so I buffer with crushed coral in the filter. Liquid tests show the real numbers, strips just guess.
Wind
Posts: 21
Joined: Wed Oct 23, 2024 5:25 pm

Re: best discus tank water testing

Post by Wind »

Thanks for the advice, everyone. Gonna order a Salifert kit and a TDS meter today. Appreciate the help!
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Dubson
Posts: 16
Joined: Sat Dec 02, 2023 4:17 pm

Re: best discus tank water testing

Post by Dubson »

Good call on the Salifert. I chill with weekly tests now but started daily like you. My 90 gallon's got 8 Discus, bare bottom, and a UV sterilizer. pH stays at 6.8 with peat granules in the sump.
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Kargo
Posts: 22
Joined: Thu Feb 10, 2022 9:44 pm

Re: best discus tank water testing

Post by Kargo »

Don't forget GH testing if you're using RO. My Discus bred once I got GH to 6 dH. Tank's 100 gallons, heavy plants, and a canister filter. Liquid tests saved me from a crash last year.
Silvan
Posts: 13
Joined: Thu Oct 10, 2024 6:16 pm

Re: best discus tank water testing

Post by Silvan »

I'm new to this, but my LFS said strips are fine. Got a 40 gallon with 3 young Discus, HOB filter, and no plants. Should I still switch to liquid tests?
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