setting up a kalk reactor that's not tied in to auto top off??


New member
I'm planning on adding a kalk reactor to my 38G system.

Today, everything is hidden in the stand. Since the tank is small, I manually add topoff every day.

I'd like to do a kalk reactor to keep things stable, but am wondering how I'd set it up without integrating it into a top off system (which I dont' have room for).

Any ideas? Since I do manual topoff, the water volume wouldn't need to be huge going into the sump from the reactor. Could I just open it every so often and add water??


New member
I think the water volume inside the reactor needs to stay about the same (i.e. full) for it to work properly...generally speaking, water gets pumped into the bottom and out the top where the water is fairly clear.

You could perhaps use a small top-off reservoir of fresh water to hold about a day's worth of top-off (or however much you can fit) and then add to that periodically.

The thing is, I don't think any of these reactors include a mechanism to push water through...even the pump-based ones simply use the included powerhead as a mixing device. Water still needs to be pushed through or pulled through from somewhere else.