View Single Post
Old 01/12/2008, 02:29 AM   #1
madadi's Avatar
Join Date: Apr 2007
Location: Morton grove, IL
Posts: 3,975
Question kalk and vinegar??

so i read somewhere that kalk (calcium hydroxide) reacts with CO2 in the water to form free calcium + bicarbonates, great.
BUT, and this is the part i did not know. if you drip too much kalk to keep your pH up, because your running a calcium reactor lets say, without enough CO2 in your water, the outcome of the chemical reaction is not calcium and bicarbonates but carbonates.
carbonates are not good in the water column because it will react with the same calcium you just added to the tank to produce calcium carbonate, an insoluble form of calcium sometimes producing a "snow" affect in the tank. even worse, this is from experience, the calcium carbonate binds with aragonite in your sand turning it into a flat rock! ya calcium reactors produce access CO2 but not enough to prevent hardening of the substrate for me. im afraid to increase the effluent rate as to not decrease the pH further, but maybe thats exactly what i need because the extra CO2 will allow more free calcium and bicarbonates to exist in the water column and stabilize the pH better?

here is the good news if that gave you a headache and the question i want to bring up in this thread for discussion. you can add some vinegar to your RO reservoir to pass trough the kalk reactor, OR just premix the kalk, RO water, and vinegar when you dose and add that to the tank.
apparently, acetic acid (also vinegar) dissolves the calcium and bicarbonates without the limiting factor CO2 at an ideal 1:1 ration. this will prevent carbonates to form, therefore calcium to drop out of solution, hardening your sand, AND lowering your pH further.
sounds perfect, but wait there is more. the left over acetate ions from the vinegar provides carbon for bacteria that feed on nitrates from the water! kind of like vodka dosing. if we can dose a known beneficial bacteria periodically like that in ultralith system to prevent a bad bacteria that can also feed on carbon over taking the tank, its a win win scenario and worth a try in my opinion, or am i way pass my bad time and dreaming up BS.



Current Tank Info: Glass box.
madadi is offline   Reply With Quote