View Full Version : Low General Hardness, w/ high KH

10-18-2003, 09:08 AM
I have a two month old, 42 gal tank with four cichlid's. My current GH (general hardness) is 90ppm with KH of around 300ppm. This is after my last water change. I have had my GH as far as 120ppm. I have been told to add marine salts to raise the GH. This does not seem to work. I have added and added. I am just afraid that I will add too much???

The good news is that my PH, KH, Ammonia, Nitrate are all excellent. My fish seem to be happy.... except for the "Chicken Dance" they do every so often. Fish look very heathy and eat like crazy.

Is there a way to get my GH up safely to at least 200ppm? How much salt can my fish tank take?

Thanks for your cooperation.

10-18-2003, 08:41 PM
Hi and welcome, Jackson

Sounds like your tap just happens to have a much higher KH than GH (since when you changed the water the GH went down). As you've discovered, sodium alone has no effect on GH (or on KH, for that matter).

Since your fish are doing well and your pH is good and stable (high KH), I wouldn't be concerned about trying to adjust the parameters so much. I'm assuming you have Rift Lake cichlids. If that's the case, they'll nevertheless do ok in lower GH water, as you've already seen. Softer water might affect spawning somewhat; but that aside, I think they'll remain just fine with they get from the tap.

Besides, I have no idea about how to increase GH without affecting the KH, except maybe add calcium chloride (which I probably wouldn't do if I were dealt those parameters and my fish were doing well).

10-19-2003, 07:31 AM
Thanks for the info. This eases my mind and helps me understand more. I am not looking to breed or anything like that. I will look into getting some good hard water for the next water change (just to trying to put the fish into there regular environment). My first goal is maintaining this healthy tank.
I actually do not know exactly what type of Cichlids I have… after reading your comments and reviewing other threads; I need to do some research and find out more about my fish and what they exactly are? Do you recommend a site with good pictures for examples?

Again, the fish seem to be very happy and the water is amazingly great. I really can’t take a lot of the credit for the tank conditions; because I really believe that the filters are doing most of the work. I started this tank with a “sump style” filtration system. It’s amazing how easy they make it for us…

Thank You,

10-19-2003, 08:07 AM
Here's a link to a gallery which groups cichlids geographically:


Because you're striving for hard water, I had assumed you keep African cichlids (from the Great African Lakes, not the riverine species).

With the noted exception of breeding, water hardness and conductivity are not nearly as important as pH and its stability with African Lake cichlids (speaking generally, as some genera appear to be more sensitive to given pH ranges than others.)

By the way, are the parameters you cite indeed pretty much those of your tap? Marine salts contain carbonates (which don't affect GH but rather KH), hence the question.