These skimmers were designed and built by hobbyists in Berlin and have been used for many years. Water chemistry is of utmost importance in both types of systems. Somewhat surprising perhaps, is the redox which varies between 180 and 195 mV as measured with a silver calomel probe. However, it is very difficult to compare redox values from one tank to the next due to innumerable variables such as probe type and pH, so any comparisons between aquariums are almost useless. Ozone is not used in this system.
Activated carbon is used every three weeks for a period of a few days and is then removed.
Hair algae must of course, be totally absent before any hard corals are introduced to an aquarium. At present the system contains over 24 specimens of hard corals representing 11 different species. These specimens are all growing and spreading over the rock. Millepora sp., Favites sp. and Pachyseris sp. The tank contains also Tridacna sp.