I have been using this top-off system for 2 years now with no problems what so ever, as a matter of fact it is my top-off/kalk reactor. In the pic I left the
kalk reactor part off. if you are going to make it into a kalk reactor you just need a
power head, cut about one foot from the plug because you are going to need it later, drill a hole on the lid sligtly bigger than the cord of the PH, put a gromet in the hole, stick the power cord through the holeleaving the Ph inside the bucket, wire the plug back in and plug it into a timmer and WOALA. One pic is the diagram of the set up, ythe ther pic is how to wire the DC air pump.
