[reefburnaby]

Hi,

There isn't anything wrong with using RO water with a CA reactor. The problem is that it would have similar calcium replenshing rates as a kalk dripper or a kalk reactor would have. On the rare occasion, both system may not be able to replenish calcium fast enough because they are based on dripping in super saturated calcium solution at the rate of evaporation. If you evaporation rate is low, then calcium addition will also be low. In this situation, I would use a kalk reactor. It provides similar performance and it is cheaper (no CO2 equipment).

Where do they differ ? Calcium reactor has low pH effluent and kalk has high pH effluent.

The important thing to note that it is not the pH that is important. Rather it is the CO2 content in the water. The calcium reactor does the following (left side are the inputs <=> right side are the products) :

CO2(g) + H2O(l) + Ca(CO3)2 <=> 2HCO3(aq) + Ca++(aq) + CO3-(aq)

CO2 = CO2 gas.
H2O = water
Ca(C03)2 = Calcium Carbonate (reactor media)
HCO3 = Bicarbonate (buffer)
Ca++ = Calcium
CO3- = Carbonate (buffer)

So, this reaction not only produces calcium in the solution, but it buffers the water. This is why we usually use CO2 in calcium reactor.

Hope that helps.

- Victor.

[ 11 January 2002: Message edited by: reefburnaby ]

[ 11 January 2002: Message edited by: reefburnaby ]