Backyard Aquaponics
A place to discuss aquaponics

Explain what Kh is?

I thought it was Kilowatt hours.

Desktop version Don http://www.csd.net/~cgadd/aqua/articles.htm

Chuck's planted aquarium calculator

I believe in this instance KH is carbonate hardness and GH is general hardness.
I only have a vague grasp of the difference between these and even less grasp of why the differences matter to us.

OK so ya got pH right?
Well ya disolved carbonates (KH) + other disolved minerals and salts (GH) = pH

So basically anything like shellgrit, coral, marble, limestone, pH up, sodium bicaronate, calcium carbonate, bicarb soda........ any of that stuff added to the water will increase the disolved carbonates (KH)

Anyway the water can only hold so much carbon right?
So its kinda like the pythagoras theorum. You find 2 parts and you can work out the 3rd.

Why care?
Well aquatic plants grow better with more co2 in the water and fish die better with more co2 in the water.
lol
Its a complicated subject really and I could probably write 50 pages on it only to have the next poster bring up another epic side to it that I had missed. One of those things that the more you look at it and try to understand.... the more complicated and crazy it gets

That's why they invented pH test kits

TC,

GH is the amountof magnesium and calcium ions in the water

KH is the amount of Carbonate ions in the water

follow me on this

adding CALCIUM chloride will raise GH but not KH
adding SODIUM bicarbonate will rasie KH but not GH
adding sodium chloride will raise neither.
adding magnesium sulphate will raise GH.

KH provides PH buffering

Steve,
That helps those of us who are new to this chemistry stuff!
Thanks.

Yep well said indeed Steve.