Rack of fish tanks  





Critical to our research program is the ability to breed and rear a variety of species of tilapia and Lake Malawi cichlids. At the University of Maryland we operate a large fishroom with more than 300 aquaria.

Most of the aquaria are on a single recirculating aquacultu re system, which maintains a high water quality. Overflow from each aquarium flows by gravity through a large drum filter to remove particulates.

It then passes into a 2000 gallon sump filled with pasta-shaped plastic biofiltration media. The surfaces of these biofilter beads are covered with bacteria which convert the nitrogenous fish waste (ammonia) to a much less toxic form (nitrate). The nitrate is continuously flushed from the system by addition of fresh water (about 500 gallons per day).

After the biofilter, the water is pumped through a set of UV sterilization filters to reduce the level of harmful micro-organisms returned to the tanks. The system is constantly monitored for temperature, pH and salinity.

We have a separate nursery room based on standard zebrafish culture racks. Eggs and larvae are incubated in small boiling flasks which allow us to simulate the flow of water they would experience if they had been left in the mother's mouth.


Baby room


Drum filter

Bead filter


Main water pumps

UV filters

UV treatment system

Happy fish!