KH low, GH high with RO water - How to adjust properly?

distant2nd

Recently upgraded my kitchen sink and added an in-line RO system. Tap water had too many hard minerals in it, so wanted to neutralize it before adding new fish to the tank. 55 Gal freshwater tank. Using API test strips, KH is reading 40 PPM, GH is reading 180 PPM. PH is somewhere between 6.5 and 7.0. I initially read about Seachem Equilibrium (the tank has live plants too), but didnt raise the KH or PH much at all. I added about 2.5 teaspoons of Alkalinity Buffer, which raised the GH from 140 to 180, but didn't budge the KH, and raised the PH a little, from 6.5 to around 7.0. I know that PH, Nitrites and Nitrates are generally the bigger concern, but I'm worried about PH spikes/instability, as our water is local reservoir water, where our old house was serviced by American Water, which had balanced water coming into the house.

Right now the only resident of the tank is an 11 year old cory. Since her tankmate recently passed away, we want to repopulate the tank, but really want to stabilize this water first going forward, as not everything is as hearty as a cory. So, how do I get the KH up without raising the GH? You'd think RO water would be very soft, but unless these test API test strips are junk, even the RO water is testing GH at 60 ppm but KH close to 0 PPM.
 

Fishstery

Recently upgraded my kitchen sink and added an in-line RO system. Tap water had too many hard minerals in it, so wanted to neutralize it before adding new fish to the tank. 55 Gal freshwater tank. Using API test strips, KH is reading 40 PPM, GH is reading 180 PPM. PH is somewhere between 6.5 and 7.0. I initially read about Seachem Equilibrium (the tank has live plants too), but didnt raise the KH or PH much at all. I added about 2.5 teaspoons of Alkalinity Buffer, which raised the GH from 140 to 180, but didn't budge the KH, and raised the PH a little, from 6.5 to around 7.0. I know that PH, Nitrites and Nitrates are generally the bigger concern, but I'm worried about PH spikes/instability, as our water is local reservoir water, where our old house was serviced by American Water, which had balanced water coming into the house.

Right now the only resident of the tank is an 11 year old cory. Since her tankmate recently passed away, we want to repopulate the tank, but really want to stabilize this water first going forward, as not everything is as hearty as a cory. So, how do I get the KH up without raising the GH? You'd think RO water would be very soft, but unless these test API test strips are junk, even the RO water is testing GH at 60 ppm but KH close to 0 PPM.
Ditch the test strips. If your RO unit is working properly and you set it up properly than kh and gh should both be 0 and pH should be neutral. When converted to degrees your gh is about 4 which isn't right. However test strips are junk anyways and that could be giving you faulty readings. Pick up an API liquid kit for kh and gh and retest. You want to pick your kH up to at least 2 dkh, to ensure no ph spikes. I would get nilocg's gh and kh booster on Amazon to remineralize instead. It's two separate bottles so you can adjust kh and gh independently and it comes as a ready to dispense liquid which in my opinion makes for super easy dosing. I use it in my high tech that I run RO on. I also use the API liquid test kit with no issues. Not to mention the liquid kit measures in degrees not PPM which is the basic unit of measurement that most hobbyists use when discussing gh and kh.

Equilibrium does not raise kh only gh.
 

distant2nd

Ditch the test strips. If your RO unit is working properly and you set it up properly than kh and gh should both be 0 and pH should be neutral. When converted to degrees your gh is about 4 which isn't right. However test strips are junk anyways and that could be giving you faulty readings. Pick up an API liquid kit for kh and gh and retest. You want to pick your kH up to at least 2 dkh, to ensure no ph spikes. I would get nilocg's gh and kh booster on Amazon to remineralize instead. It's two separate bottles so you can adjust kh and gh independently and it comes as a ready to dispense liquid which in my opinion makes for super easy dosing. I use it in my high tech that I run RO on. I also use the API liquid test kit with no issues. Not to mention the liquid kit measures in degrees not PPM which is the basic unit of measurement that most hobbyists use when discussing gh and kh.

Equilibrium does not raise kh only gh.
Thanks for that info! I got an API liquid test, and while the KH reading was 7 drops, which seems to suggest a KH of 7, I put in literally over 100 drops on the GH size and the color still wouldn't get to where it would indicate it was done. I did get it from a mom and pop shop that looks like it is stuck in 1982, so who knows how old that kit is =D.

I'll check out the nilocg's booster. I'm assuming only way to lower GH is water changes with the RO water?
 

Fishstery

Thanks for that info! I got an API liquid test, and while the KH reading was 7 drops, which seems to suggest a KH of 7, I put in literally over 100 drops on the GH size and the color still wouldn't get to where it would indicate it was done. I did get it from a mom and pop shop that looks like it is stuck in 1982, so who knows how old that kit is =D.

I'll check out the nilocg's booster. I'm assuming only way to lower GH is water changes with the RO water?
I would probably look into another test. Also, put a the vial over a piece of white paper and look straight down the tube to determine the color change. The way those tests work can be tricky, but that's the most accurate way to read it. When you look through the vial from the side the color is much more diluted on these tests than an overhead view of the vial with the lid off. You may actually be getting a color change with less drops and didn't notice because of the way you were looking at the vial. You are correct that you can lower gh by water changes with RO given your RO is yielding 0 gh (which it should).
 

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