• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

question on increasing ferts

Thanks for sharing that explanation Darren, that makes perfect sense now. I'm pretty sure it has made a difference, so Mg must have been the issue.


Sent from my iPad using Tapatalk
 
If the water hardeness is 9kh does that mean there is enough Mg in the water?
 
Hi all,
If the water hardeness is 9kh does that mean there is enough Mg in the water?
The dKH is a measure of carbonates (as HCO3-), these will have come from the dissolution of a salt, usually it will be CaCO3, because CaCO3 is the least soluble carbonate and builds up into large geological deposits under suitable situations for deposition ("limestone"). But the source of the carbonates can be other compounds like NaHCO3 (sodium bicarbonate), and doesn't necessarily add any dGH at all.

General hardness (dGH) is a measure of the divalent cations, Mg++ and Ca++, but it doesn't tell you whether it is Ca++ or Mg++. In the UK a lot of aquifers are pure CaCO3 (often chalk), and this doesn't contain any magnesium. Limestone make have undergone dolomitization after their deposition, where some of the calcium has been replaced by magnesium. This is the situation in the magnesian limestones in the UK that run N. from Nottingham to Durham or the Italian Dolomite Alps.

Magnesium containing rocks usually originate from either volcanic action (like in New Zealand or Lake Tanganyika) or from evaporite deposits (like "Epsom salts"). Unless you know that your water contains magnesium you need to add it.

cheers Darrel
 
Hi all, The dKH is a measure of carbonates (as HCO3-), these will have come from the dissolution of a salt, usually it will be CaCO3, because CaCO3 is the least soluble carbonate and builds up into large geological deposits under suitable situations for deposition ("limestone"). But the source of the carbonates can be other compounds like NaHCO3 (sodium bicarbonate), and doesn't necessarily add any dGH at all.

General hardness (dGH) is a measure of the divalent cations, Mg++ and Ca++, but it doesn't tell you whether it is Ca++ or Mg++. In the UK a lot of aquifers are pure CaCO3 (often chalk), and this doesn't contain any magnesium. Limestone make have undergone dolomitization after their deposition, where some of the calcium has been replaced by magnesium. This is the situation in the magnesian limestones in the UK that run N. from Nottingham to Durham or the Italian Dolomite Alps.

Magnesium containing rocks usually originate from either volcanic action (like in New Zealand or Lake Tanganyika) or from evaporite deposits (like "Epsom salts"). Unless you know that your water contains magnesium you need to add it.

cheers Darrel
if i dose epsom salts and water already contains Mg will this cause any problems to fish or plants?
 
Back
Top