I was sitting in my living room, enjoying one of my 55 gallon African cichlid tanks when I noticed that several fish were all in a row, swimming their little hearts out but not really going anywhere. Upon closer examination, I noticed that they were all Nimbochromis Livingstonii which are known for needing a large area to swim. In fact, it is recommended that they have at least a 6 foot long tank when they get full size to ensure they have a long stretch to swim in. I was a little puzzled by their behavior until I realized that they had found the current generated by the power head and were utilizing it to swim without needing to stop. They were literally swimming for hours on end! The only problem I could see was that the “sweet spot” where they could swim at the correct speed was kind of small so they were all very close together and not all five could participate at the same time.
I decided I would try to make a steady current of water that they could all use at the same time. After trying a few different ideas, I came up with a solution that really seems to give them an “endless aquarium”. Here are the parts required to make the endless aquarium setup. I did it in a 55 gallon 4 foot tank, but I guess you could do it in virtually any tank:
2 power heads (with included mounting hardware)
2 lift tubes for an under-gravel filter (Make sure to use the top caps with the grills)
2 suction cups
Step 1: Drill holes large enough for the suction cup nipples to fit tightly into. The holes should be on the same end as the top caps but on the opposite side of the output top cap output (see diagram 1) Alternatively, you could use fishing line or silicone to attach the suction cups to the lift tubes.
Step 2: Trim the lift tube so that the lift tube and power head will be slightly shorter than the depth of the tank FRONT to BACK (not height top to bottom). On a 55 gallon, I had to trim the tube to nine inches. 9 inches, plus 2.5 inches for the power head fit nicely into the 12 inch depth of the tank. See figure 2 for a better idea of what you are trying to achieve.
Figure 2: View from the TOP of the tank
Step 3: Combine the power head and lift tube. Now mount these SIDEWAYS in the tank as shown in figure 2. The idea is to create a whirlpool effect. The suction cup attached to the lift tube will secure one end of each assembly, and the mounting hardware (whether a hang on the side type or suction cup type) will secure the other end. Make sure the power heads are on the front and back as shown in figure 2. You can use the venturi effect on one or both of the power heads by attaching an airline to suck air from above the water line. I only use the venturi effect on the rear power head so the bubbles do not block a good view of the fish. You can adjust the flow output with the directional power heads to really dial in a good steady stream for your fishes. You can also adjust the depth below the water surface to see what works best. Mine is about 3 inches below the water line.
Step 4: Plug in the power heads and watch your fish go for a swim. My Livingstonii love this setup and they really take advantage of it. I also find that my mbunas enjoy swimming into the stream and going for a ride! They will do it over and over again – its great.