I'm running a 400 gallon system that's recently been cycled.
I test chemistry daily. My PH is hovering around 6.8 with the use of egg shells and oyster shells in grow beds. When I started the system, my PH was around 5.8 and I had trouble starting the cycle due to the lower PH. I bumped up the PH with some lime and things moved forward.
It's been a few months and I picked up a GK and KH test kit. Using the KPI kit, you have to count drops and watch for a color change. After a few repeated tests, I think I got the process down and somewhat accurate.
Here's my results.
GH 23 drops = 411.7ppm
KH 2 drops = 35.8 ppm.
I've read quite a few topics on the relationship of GH, KH and PH, but can someone give me some advice to improve my water quality at this point?
My fish seem to be ok but my plants (lettuce and tomato) seem to be struggling.
A low KH is bad. Nitrification lowers carbonate levels. you will need to supplement. I have been adding calcium carbonate and potassium carbonate but i'm switching over to a new product. ROCK DUST. I cant seen to find out a hole lot about people using in in aquaponics but i contains everything that i had been trying to supplement. I bought Glacial Rock Dust. There is also rock dust from portable farms. They have been using it with great success this year.