Kalkwasser dose? How much?


This is incredibly confusing! How many onces of the mixutre do you guys dose per night? I have a 150 and 55 gallon tank. Right now I dose about 8oz into the 150 per night and 3-4 oz for the 55. Any help would be appreciated.
Hi all water top offs are with kaulwasser, this is what I do , all water changes with ro water, kaulwasser must be driped SLOWLY, so this is why I run this almost constantly dripping, I loose about half to three quarters of a gallon per day. This is my method....cya

nm reef

Active Member
I may be wrong but its my understanding that its best to use 1 tablespoon of kalkwasser per 1 gal of top-off.....I just recently started using this method for my 55 reef......I add approx 1 gal per day
mix the kalk with ro water in the morning.........that night after lights out I drip it in the tank with a home made doser(IV tube attached to a 1.5 gal jug........needs to be added slow ....maybe some one can help ya more
I started with the IV bag and I found I needed more top off than that so, I got a two and a half gallon jug of RO water,Drilled small hole about an in from the bottom[they suggest making kualwasser up 24 hrs in adv and, not to use the lower sedament] , thats why I put the hole an inch up, and inserted small plastic hose connecter and hotglueing to seal it,so then you could add a piece of aquarium hose , like for a bubbler about 2 ft piece of hose and put a small valve inline and that way I could adjust flow, I keep two of these jugs ready ,When ones dripping the others waiting , and just swich, works well for me / also I mix one teaspoon per gallon...cya ;)

nm reef

Active Member
Mine is almost identical to fixit's..........got the iv bags from a friend of the wife at the hospital............cut the tube off and silicone that to a 1.5 gal (new) water bottle(square) from the store where I buy my ro water.......I too placed the tube about 1-2 inches from the bottom.............workin good so far..... :cool:


Active Member
Mine is pretty much the same too. I used a 2 gal container drilled holes in the sides near the top across from each othe to run a piece of rope and hanger. I got a i/v line which came with a roller adjuster for drip rate and a sharp plastic end that I inserted into a smaller in diameter hole I drilled in the bottom of the container. That created a great seal by itself but I also put wax around it to give it an extra seal. The length of the sharp plastic end sticks up about an inch inside the container stopping any sediment from dripping out.


Kent makes several sizes of drip systems for not much cash. The 5 gallon size is only about 25 bucks. You might consider using a two part calcium buffer system instead of kalkwasser, as kalk has a very high ph that can lead to problems if dosed wrong. It is cheaper than a two part buffer system, but if you put in too much, you could easily crash your system. I'm not saying kalk doesn't work, but there are drawbacks to it.


I understand your confusion. I was confused for a very long time because I was looking for the right way to do this. What I found is that there is no one right way.
As stated above try to add all of your top-off with Kalkwaasser water, and drip it in slowly.
How I decided how much Kalkwasser powder to add to the mixture and how slowily to drip it was by testing my water. I wanted a Ca+ reading of 450 and I did not want my pH to go over 8.2.
I add 2 teaspoons per gallon of DI water. Let it sit over night. Then I siphon off the clear fluid in the middle. It forms a crust on the top and a white powder on the bottom. I use 2 liter IV bags which I have hooked together, a dialflow drip set which give me a very accurate drip rate(not really needed but I work in a hospital and I use to be an RN).
I have been exploring buying an old IV pump to drip this stuff in. (Various websites sell them, as well as action houses) You can buy them for between $50 and $150.
Good luck!