The dimensions of the main aquarium are 180x60x60 cm. A section of glass is bonded diagonally into the left rear corner resulting in a space of 15 litres. This space is filled with 10 litres of bio balls and is used as a drizzle-filter. There is a 5 cm. thick layer of foam on top of the drizzle-filter. It prevents dirt, leaves, food particles or small fish from entering. The water from the drizzle filter flows into an 80 litre, 4 chamber bio-filter at the bottom of the aquarium. The first chamber is equipped with a cotton/wool filter, the second and third with foam material, and the fourth with 6 litres of Siporax (a special glass filter material). A 2000 l/hr. pump and a heater are installed in the main portion of the tank. The aquarium is illuminated by 3 58 watt florescent tubes controlled by a timer. Total daily lighting amounts to 11 hours. During this time, the CO-2 system is also switched on by a single solenoid valve. The gravel is raised approximately 1 cm. by an EHEIM ground flow system. Some of the water flowing in the tank is directed through this ground flow system. The sides and rear of the aquarium are decorated with cork. The aquarium has been in operation since March, 1998. Problems with algae occurred initially. There was a significant growth of thread and brush algae. However, the algae disappeared almost completely be adding 5 young Siamese Ruesselbarben and a CO-2 system. Since then, the maintenance of the aquarium has been limited to weekly cleaning of the foam material in the drizzle-filter, a 10% water change every 10 - 14 days and cleaning of the cotton/wool filter as required (approx. every 2 - 3 weeks). Additional maintenance includes thinning out the plants every 2 - 4 weeks. Cleaning the glass and suctioning out contaminants has only been required twice so far.