Two question: GH of tank & community fish?

[Hokieokieamy]

Hi guys,

If the water in my tank was 129 ppm, that would be 9 GH, right? So a slightly hard water?

Also on Liveaquaria website where you can buy fish, it says freshwater community fish do best at GH of 4-12. What is exactly meant by “community fish”?

Thanks!

 

[Essjay]

That website just means fish that are commonly kept together. But I'm afraid that is not good advice. It is impossible to say that every community fish should be kept at those levels. Hard water community fish should not be kept in water with a GH as low as 4, and soft water community fish should not be kept in water as hard as GH 12. Each species has its own GH range.
Personally I would ignore Liveaquaria and go by the hardness ranges given on Seriously Fish.

129 ppm is actually 7.2 dH, which is at the top end of soft, bordering on 'middling'. You can check the conversion by using the forum's calculator https://www.fishforums.net/aquarium-calculator.htm Hardness is near the bottom, ppm is listed as mg/l CaCO3.

 

[Hokieokieamy]

That website just means fish that are commonly kept together. But I'm afraid that is not good advice. It is impossible to say that every community fish should be kept at those levels. Hard water community fish should not be kept in water with a GH as low as 4, and soft water community fish should not be kept in water as hard as GH 12. Each species has its own GH range.
Personally I would ignore Liveaquaria and go by the hardness ranges given on Seriously Fish.

129 ppm is actually 7.2 dH, which is at the top end of soft, bordering on 'middling'. You can check the conversion by using the forum's calculator https://www.fishforums.net/aquarium-calculator.htm Hardness is near the bottom, ppm is listed as mg/l CaCO3.

Great! Thanks so much and I will check out that website

 

[Colin_T]

There is 17.9ppm in 1dGH

0-50ppm = very soft water
50-150ppm = soft water
150-250ppm - medium hardness
250-350ppm = hard water
350-450ppm = very hard water
450+ppm = extremely hard water.