kH and gH

[Erk]

I have never really paid attention to these tests.....is a kH=4 and a gH=8 good for discus, or do I need to do something to change these values? and what do I do to change them? haha :?

Thanks a lot

[Merrilyn]

Those readings are fine Erk for raising discus. If you want to breed them you may need to lower the KH and GH by adding RO water to the tank.

KH simply translates as dissolved calcium in the water. Fish need some calcium to grow strong bones. GH relates to general hardness, the overall hardness of your water. Your readings show that you have soft water which is ideal. Fish like African cichlids prefer hard water with a high pH reading. We sometimes jokingly refer to it as liquid rock.

Fortunately, you don't need to do anything :P

[Erk]

Thanks Merrilyn! Thats great news! I am only trying to raise these beautiful fish, not breed them, and Im glad to hear I dont need to purchase an RO unit

Thanks a lot :D

[Hail2Pitt02]

Those readings are fine Erk for raising discus. If you want to breed them you may need to lower the KH and GH by adding RO water to the tank.

Ok....this perked a few questions for me.....If the KH was lowered with R/O water lets say, wouldn't that leave the tank susceptible to PH swings? How do you find that magical balance between soft, slightly acidic water and stability?

[Merrilyn]

I'ts a very fine balancing act Pitt.

Constant testing and constant water changes till you know exactly how your water behaves.

If the water is too hard, and the pH too high, the eggs can't be fertilised. So soft acid water is called for here. Once the eggs hatch, and the fry are free swimming, you can gradually allow the water to become a little harder.

Now that's a very simplified version of what happens, but if you would like a more scientific explanation, there is a wealth of information on the net. Just google osmotic pressure.