Kalk is calcium supplement. It's kind of magical. If you drop it into ro/di as a powder, and swish it just once, only 2 teaspoons of it per gallon WILL dissolve. You can't overdose, in ro/di. If there's any left, it'll sink to the bottom of the container and dissolve ONLY when more ro/di comes into the container.
Now if you have an ATO, you set this as your topoff reservoir and it delivers kalk to your tank at a rate very nice for stony corals and clams. [There is a way to hype it a tad with vinegar, but that's another story.]
If you have a 75 gallon tank or smaller, completely packed with stony corals, this is probably all you can use. If larger than 75 AND PACKED, you may need a calcium reactor, which is a whole 'nuther story, too. Calcium reactors, for big reefs, are sometimes helped out by a kalk feed or kalk reactor, if they need just a shade more.
Now, there are a couple of ways to get measured amounts of kalk into your tank---just dumping it into your ro/di topoff container, lidding it tightly (use rolled up paper towel to stop air getting to it] and letting the ATO deliver it AS the topoff [it IS still fresh water, just fresh water with a lotta calcium in it.]
Suppose you are so cramped for space you really need to miniaturize, a kalk reactor, which looks a lot like a GFO reactor, is designed to feed an airline tube-sized tube through your kalk supply to your tank. Frankly, I had one of these, and got rid of it, because it was so much simpler just to put it into the topoff container. The thing had a kalk stirrer---nice, except it only needs to be stirred once, then allowed to sit and settle, and I had 3 expensive stirrers break down. When I found out I could just dump the stuff straight into the topoff barrel and skip the reactor and stirrer, I was a little put out.
In either case, whether you put the kalk into your topoff as I do, or whether you run this device to put a bit of kalk in as it goes through, it all works via an ATO system of some sort.
An overdose is just a milky white version of a topoff accident---mostly a problem because it IS fresh water altering your salinity if it goes too far. I've had a few accidents involving a coral reef, with no losses whatever. It's pretty safe. I will also say almost all the accidents were due to the kalk reactor, not the regular topoff.
Kalk will NOT raise your calcium level: it can't do that for you. You set your parameters by dosing separate supplements to reach [magnesium 1300, calcium 420, and alkalinity 8.3], THEN set your ro/di kalk mix to going, and your tank will hold those levels so long as the topoff barrel holds out. I've managed to sustain those levels for 3 months with no other adjustment, simply by adding 2 lbs of Mrs. Wages' Pickling Lime to a 32 gallon Rubbermaid Brute trashcan full of ro/di, to which I added more water as it ran low.
Great for handling a stony reef while you go on vacation.
Pretty safe. If you overdose badly, one tablespoon of Schweppes' Bar Soda per 50 gallons will usually fix the ph spike (the stuff comes in at ph 12) ---but the tank will self-correct really fast without that.
Pretty cheap too. The Mrs. Wages is 5 dollars for 2 pounds. That's 3 months worth in a 50 gallon reef.
This is NOT to start before you have a lot of corals---they'll be fine with your ordinary water changes, since your salt mix, if you're using a reef salt, will have calcium in it.
But once you notice that you're spoonfeeding calcium nearly daily and still needing more, you have two choices---well, three. You can add pretty expensive calcium by hand, you can do kalk, or you can use Two-part, which is also a good way to go. I personally like kalk best only because it's what I've always done.
When you reach that magical point where clams are building shell or stony coral is making new branches hand over fist, you are at that point of choice. Two-part or kalk, and if kalk, reactor or no-reactor.
Now if you have an ATO, you set this as your topoff reservoir and it delivers kalk to your tank at a rate very nice for stony corals and clams. [There is a way to hype it a tad with vinegar, but that's another story.]
If you have a 75 gallon tank or smaller, completely packed with stony corals, this is probably all you can use. If larger than 75 AND PACKED, you may need a calcium reactor, which is a whole 'nuther story, too. Calcium reactors, for big reefs, are sometimes helped out by a kalk feed or kalk reactor, if they need just a shade more.
Now, there are a couple of ways to get measured amounts of kalk into your tank---just dumping it into your ro/di topoff container, lidding it tightly (use rolled up paper towel to stop air getting to it] and letting the ATO deliver it AS the topoff [it IS still fresh water, just fresh water with a lotta calcium in it.]
Suppose you are so cramped for space you really need to miniaturize, a kalk reactor, which looks a lot like a GFO reactor, is designed to feed an airline tube-sized tube through your kalk supply to your tank. Frankly, I had one of these, and got rid of it, because it was so much simpler just to put it into the topoff container. The thing had a kalk stirrer---nice, except it only needs to be stirred once, then allowed to sit and settle, and I had 3 expensive stirrers break down. When I found out I could just dump the stuff straight into the topoff barrel and skip the reactor and stirrer, I was a little put out.
In either case, whether you put the kalk into your topoff as I do, or whether you run this device to put a bit of kalk in as it goes through, it all works via an ATO system of some sort.
An overdose is just a milky white version of a topoff accident---mostly a problem because it IS fresh water altering your salinity if it goes too far. I've had a few accidents involving a coral reef, with no losses whatever. It's pretty safe. I will also say almost all the accidents were due to the kalk reactor, not the regular topoff.
Kalk will NOT raise your calcium level: it can't do that for you. You set your parameters by dosing separate supplements to reach [magnesium 1300, calcium 420, and alkalinity 8.3], THEN set your ro/di kalk mix to going, and your tank will hold those levels so long as the topoff barrel holds out. I've managed to sustain those levels for 3 months with no other adjustment, simply by adding 2 lbs of Mrs. Wages' Pickling Lime to a 32 gallon Rubbermaid Brute trashcan full of ro/di, to which I added more water as it ran low.
Great for handling a stony reef while you go on vacation.
Pretty safe. If you overdose badly, one tablespoon of Schweppes' Bar Soda per 50 gallons will usually fix the ph spike (the stuff comes in at ph 12) ---but the tank will self-correct really fast without that.
Pretty cheap too. The Mrs. Wages is 5 dollars for 2 pounds. That's 3 months worth in a 50 gallon reef.
This is NOT to start before you have a lot of corals---they'll be fine with your ordinary water changes, since your salt mix, if you're using a reef salt, will have calcium in it.
But once you notice that you're spoonfeeding calcium nearly daily and still needing more, you have two choices---well, three. You can add pretty expensive calcium by hand, you can do kalk, or you can use Two-part, which is also a good way to go. I personally like kalk best only because it's what I've always done.
When you reach that magical point where clams are building shell or stony coral is making new branches hand over fist, you are at that point of choice. Two-part or kalk, and if kalk, reactor or no-reactor.
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