KH Problems

Hello, this is my first post in these forums, lately I have encountered some problems with my KH in my medium to heavily planted 190l tank. I have a pressurized co2 system with ph controller set to 6.5.

Now normally I dont usually test my water, I do regular water changes of 25% every week. As of lately, I noticed that plants didnt pearl as they did before. After some water testing I found out that my kh is only 1 to 1.5, this leads to a low co2 count.

I have tested the tap water which I use to do my water changes, and the kh is 4.

How can I stabilise the kh of my tank so that I can have a larger amount of dissolved co2 in my tank.

 

Re: KH Problems

I have bought Bicarbonate of Soda so that I can raise the KH, but if I add it, it will also raise the PH. If I add more co2 to bring the ph down, will the kh decrease too, ending up in a endless cycle?

Last time I had checked the kh of my tank, it was stable at 6dkh and I was running at about 20ppm to 25ppm co2. One thing I have done lately was to double the amount of light I have over the tank, ending up with 152w of light, around 3wpg.

I have took a sample of my tank water, left it 24h to standby, and after I checked the ph, it was at 7.65, dont know if from this you can calculate the co2, but I have read it somewhere in these forums.


Below are the water parameters as of this morning, is it possible that the KH is crashing cause I am reducing the PH so much?

Tap Water Parameters

PH 7..5
KH 6
GH 17

Aquarium Water Parameters

PH 6.5
KH 1
GH 16