Quote:
|
Originally Posted by Delphinus
You can drip kalk without a kalk mixer. A kalk mixer just automates the process a little, you make a super saturated solution, the powerhead or whatever mixes it up from time to time to ensure you have a saturated solution being dripped in. You do sort of need some kind of automated water topup with a kalk mixer as it will be constantly dripping so this water needs a constant supply (e.g. RO water reservoir).
Obviously, you cannot drip more kalk into your system than the water that evaporates, so the amount of kalk you can add has an upper limit. In a low consumption system this may not be a big deal, however in a high consumption system you could easily have more Ca/Alk consumed than the kalk could conceivably keep up with.
So the advantage of a kalk mixer is cost (much less expensive). The disadvantage is that there is an upper limit to how much Ca and Alk it can add to a system.
...
A calcium reactor, on the other hand, takes tank water in and puts it back. The premiss is you cycle water through a calcium substrate ("reactor media"), then you bubble in CO2 into the vessel to lower the pH just enough so that the calcium starts to dissolve. The reactor effluent then is laced with Ca and Alk.
The advantage of calcium reactor is the fact that you can "dial up" how much Ca and Alk it adds to the system. Add more corals and find your alk starting to drop? No problem, dial up the reactor to compensate. The other advantage to a calcium reactor, and this is key, if you ask me, is that once it is dialed in, it is "set and forget". No more worrying about how your Ca and Alk are doing if you go away and can't dose whatever. The disadvantage of a calcium reactor is high initial investment cost, and the CO2 will work to slightly pull down pH in the tank (which can, in some cases, lead some nuisance algaes to take off, so you have to be careful about nutrient management).
....
There's no rule saying you can't have both. The high pH effluent of the kalk, for example, can help offset the low pH of the calcium reactor effluent.
|
I am now running both on my tank. As Tony said, the kalk drip will not keep up with high ca consumption, which was the problem I was having. I was using just a kalk reactor, and even with 2-3 gallons a day evaporation I continually had to suppliment calcium and alk to keep the levels up. I now have a calcium reactor as well and the levels are stable. I do have mostly sps and lps coral which are calcium hogs. The buy in for the calcium reactor was high even as a diy project. The reg and tank are the major cost of the unit. But if you figure the long term cost of suppliments, the payback is good.
I have a couple of soft corals in my FOWLR tank and they hardly use any ca. I have never had to suppliment the levels, water changes alone are sufficient.
So the answer is really dependant upon your tank and its calcium/alk needs.