April 2010 - Kitchener Waterloo Aquarium Society

A P R I L 2 0 1 0next to the Great Wall of Foam in the tank. Yes, as it turns out,foam pre-filters have feelings too! I did, however, keep theplastic pump inlet guards in place, just in case some unluckyfish manages to jump the foam sheet and get to this side of thetank.My geeky math skills tell me that these pumps should turn overthe tank's 125 gallon water volume roughly 10 times per hour.Taking the tank cross-sectional area into account, if the flowmoves evenly through the foam filter sheet, it would travelthrough it at just under 1/4” per second. It's amusing to thinkabout how much more water movement is in this tankcompared to most other freshwater tanks, but at the same timehow it's one or two orders of magnitude less than a river or ashallow, fast-moving stream-bed. Nature may often beimitated, but it is never really duplicated.For the final assembly steps, I cemented the base PVC manifoldpieces together after the dry fit. Thank goodness it still fit intothe tank after this step! Then I added the riser pieces for thespray bars and pump inlets at either end. After playing arounda bit, I finalized the pump layout to minimize space behind thesponge but also keep the pump intakes as low as possible. Thepump housings were placed down onto spare pieces of foam inan attempt to limit vibration coupling and noise. As a sidebenefitto this, I now have room to press down on the pumpbody to separate the pump from its manifold at the short, noncemented1/2” PVC joining piece. This would be useful forpump servicing or replacement if needed.to be shorter than the other, the bottom spray bar leans in a bitto pass in front of the riser for the upper bar.Now let's make one thing clear―I can play around with sometank filtration stuff, but when it comes to the inhabitants andoverall tank style, my wife still dictated the terms. Yes, dear, itwill still be a planted tank! We reused our old CO2-injectionequipment, which consisted of a small CO2 tank, Milwaukeeregulator, and pH monitoring system with cutoff solenoidvalve. Previously, the intake to our Magnum 350 canister filtermade for a convenient CO2 reactor to dissolve and disperse theCO2 into the tank water. For this new setup, I fed the CO2 intoone of the pump intakes. The pump's impeller and the 6 feet ofPVC manifold pipe make for a good reactor as well. Once air ispurged from the system, only occasional tiny bubbles are visiblecoming out of the spray bars. I also fed the CO2 into the pumpaligned with the lower spray bar, so the majority of the CO2 isinjected into the base of the tank and not close to the surface.To finish off the remaining tank “hardware”, I filled the gapsbetween the PVC manifold tubes with Eco-Complete substrateand then placed a few mounted driftwood pieces on top. Afterthese slate pieces were covered with a final layer of substrate, itssurface ended up about 3” above the tank base. Tank lightingcomes from two 36” dual-96-watt power-compact fixtures fromthe States.For the outlet spray bars, I placed end-caps on two 3/4” PVCpipe sections and then drilled twelve ¼” holes along the lengthof each. The two spray bar risers are at different heights, so onespray bar end up being 6” from the gravel and the other isabout 6” from the top of the tank. The spray bars themselvesaren't cemented in place, so they can be twisted around, orremoved to be cleaned or replaced if needed. Since the risersaren't at the very corners of the tank and I didn't want one barOnce the tank was filled up, we started filling the tank in withsome plants from Big Al's as well as a nice plant kit from Ed“sucker4plecos” Koerner. After a few weeks of cycling, someBristlenose plecos moved in, and then a colony of 50 cardinaltetra took up residence a couple of weeks later.As far as initial impressions go, the first thing that strikes me isthat those Mag-Drive units are loud! They are mainly designedfor ponds, and while they aren't overly loud by themselves, itreally doesn't help that they are coupled via rigid PVC pipe tothe manifold and then the bottom glass of the tank. They arealso somewhat inefficient, consuming about 70 watts each 2418