Stable vs Ideal PH KH GH

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Registered Member
Jun 18, 2021
Hi All,

My Ph is 8.1, Kh 4 degrees, GH 4 degrees, out of tap water.
I measured again 24 hours later with aeration, results were the same.
I worry about my GH level and am confused by the different info from different sites.
Malawi Mayhems states that Gh should be 4-6 degrees, Cichlid guide says 7 degrees, Live Aquaria says 12-20 degrees.

Then also, I've tested for Calcium and Magnesium in my water.
Calcium measured 1.6ppm as pure ions. Magnesium measured 7.43ppm as pure ions.

For keeping a show tank, is it suffice to have stable but non-extreme water conditions rather than ideal?
Ofcourse, I do plan on regular water changes to keep it clean and replace trace elements.
I really dont think I should alter water parameters if my fish will simply adapt.
All this info about adding things to water is quite complicated.

Will I be okay with my tap parameters? or should I use a GH booster like Calcium Chloride or Magnesium Sulfate?
I think its just my GH thats the issue here.
I dont think Calcium in the water column is an issue since the fish food I plan to use has Calcium.
Apr 2, 2002
New York
Assuming your readings are accurate your water is a bit on the unusual side. Normally, one expects to see higher numbers for GH and KH for that pH level. Your water is like some of the lakes of the Sulawesi.

Fish are more sensitive to Conductivity/TDS than pH for the most part. Ans mostly softer water is lower H and harder is the reverse.

If your goal is to raise the conductivity/TDS there are a few ways. GH and KH are both part of conductivity/TDS, but so too are ions, dissolved organics etc. One can have a substrate of crushed coral. or one can use a produce like SeaChem's` Equilibrium.

Your pH is not super high, so the are many fish that will be OK in your water unchanged. You may actually have better luck with softer water fish with a higher pH than they normally have than with rift lake cichlids which can handle even higher pH levels but alse need much harder water. A lot of fish, especially farmed or tank raised, have become adapted to conditions somewhat out of the range they are found in the wild.

As a rule, it is better to work with fish that will do well in one's tap para,eters than to have to alter one's tap parameters to keep fish that will not normally thrive in one's tap parameters.