GH and KH, do I need to worry......

[michaelwgroves]

My GH is 180, and KH 120.
It seems high, but do I need to worry, everything else is fine. When I get new fish I lose a few, but the rest live forever.
I have a 3 stage RO (not in use), so can bring this down with RO. But last time I did this my plants did not like it, so I stopped.

Out of the tap I get GH 30 and KH 40. So something in the tank appears to be pulling the numbers up, is there anything in a heavily planted tank that might be pulling the numbers up. I do weekly 10% water change.
I dose CO2 which keeps the tank ph at a calibrated 6.5 Although my test strips disagree and read 7.5. I also dose daily with Tropica Specialised Nutrition. Although just run out so moving to Neutro CO2 & Neutro+

Any thoughts?

 

[Sleeveless]

I know many will chime in and mention you should be doing larger water changes. I do 50% weekly after reading and getting a ton of advice on this forum. Larger change will help remove more waste and other possible causes of increased GH/KH. I've also never had accurate PH on a test strip. I use them if I need an idea, but use my liquid strips or calibrated PH pen. Even teh pen I question sometimes so the liquid tests like API are your safest bet.

 

[GaryE]

I would have a look at my decor. Those aren't numbers to worry about, though you didn't say which species of fish are involved.

The usual culprits for a rising mineral level are the substrate and decor. Do you have any rocks or gravel in there that could be dissolving?

We all do things differently, but I never do a water change of less than 30%, and often to 40 to 50%. That's on a weekly basis.

 

[Colin_T]

My GH is 180, and KH 120.

What fish do you keep? They will determine what the GH, KH and pH should be. A GH of 180ppm gives you a lot of choice including groups 1 and 2 below.

1) Angelfish, discus, most tetras, most barbs, Bettas, gouramis, rasbora, Corydoras and small species of suckermouth catfish all occur in soft water (GH below 150ppm) and a pH below 7.0.

2) Livebearers (guppies, platies, swordtails, mollies), rainbowfish and goldfish occur in medium hard water with a GH around 200-250ppm and a pH above 7.0. Mollies need the GH at 250ppm+.

3) If you had very hard water (GH above 300ppm) then look at African Rift Lake cichlids, or use distilled or reverse osmosis water to reduce the GH and keep fishes from softer water.

 

[michaelwgroves]

Thanks for your thoughts, I'll try and up my water changes. I'm a lazy fish keeper, I know I need to do better.

It's a community tank, so mainly the fish in groups 1 & 2. Less Angels, Discus & goldfish. I also have a lot of shrimps.
I have gravel as my substrate.