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Symphysodon aequifasciatus

The hardest of all. It needs 30°C water, and high temperature lowers oxygen saturation. Tall-bodied, so a deep tank is a must, and it’s extremely sensitive to nitrate.

Temp 28~32°CpH 5.5~7GH 1~8Adult 20 cmGroup 4+Min. tank 250 LSwims middlePrice $42.86

How many fit in each tank?

The largest group where none died in 90 days. Tap water mixed with RO water (share shown per tank) · black sand · bacteria starter on day 1 · fish added on day 10 · 25% weekly water changes.

It likes soft, acidic water. Plain tap water (around pH 7.7) was too much, so this was calculated with RO water mixed in. Bigger tanks hold more water and their pH drops less, so they needed more RO water. But mixing in 90% RO water used up the buffer (KH), pH crashed and all of them died.

With plain tap water it didn’t make it to 90 days in any tank. This species needs its water adjusted specially.

30 cm cubeNot recommended — needs 250 L or more
45 cm standardNot recommended — needs 250 L or more
60 cm standardNot recommended — needs 250 L or more
90 cm standardNot recommended — needs 250 L or more
120 cm standardNot recommended — water too shallow
120 cm largeNot recommended — too much waste to add at once — cycle longer and add in stages
Design a tank with this fish →

Don’t keep with

The same rules the engine uses for tankmates.

Good tankmates

No eating or bullying either way, with plenty of overlap in temperature and pH. Fish that swim at a different level come first.

The numbers on this page come from the Water Kiwoogi simulator model; real tanks can differ.