Return Pumps

The job of the return pump is to pump water from the water reservoir under the tank (sump/trickle filter) into the aquarium. The pump included with my filter kit is the Sicce Syncra Silent 2.0 rated at 568gph or 5.9ft head. It definitely did its job being quiet, but just didn't provide the flow I was expecting. I knew I wasn't going to get the 500gph because of the 4ft of head. Basically, the pump has to not only provide the flow I need, but also lift the water from the sump on the floor to the top of the tank. So I did a little research into "flow". The most common unit of aquarium flow is the number of times the volume of your tank is cycled per hour. So 10x would mean 36gal * 10times/hour = 360gph. Most basic aquariums are good with 5x. From what I found on the forums, a good reef aquarium needs 20x flow, meaning 720gph in my tank. [[Lesson learned: let me clarify that 20x is the total flow in the display tank. Really you only want at least 10x on your return pump.]] I loved how silent my first pump was so I went to the Sicce website and found a great flow vs head graph.

After taking into account the two 90degree bends and the 1" tubing, I figured 5ft head. The Syncra 4.0 at 951gph(0head) or 12.5ft(0flow) came the closest to the flow I was needing. After ordering it online, I decided to experiment and siphon 5gal of water into a bucket and have it pump it all back into the tank. I fully realize this is not a perfectly accurate way to rate the flow of my working aquarium, but it was definitely the easiest. It took 32seconds which calculated to 560gph. Way short of the 720gph that the forums recommended, but still good flow. I then set it up in the tank and loved the way the debris on the bottom got picked up while leaving the sand in place. The problem: it was way too loud for my living room. I took care of the gurgling and will explain that in my next post. I left it for a whole day only hearing the (loud) low hum of the pump. Finally, I decided it just wasn't working for me. If in the future I need more flow, I will add a wavemaker setup. After having a Syncra 2.0 that was silent but fell short on flow and a Syncra 4.0 that had great flow but too loud, I set out for the local fish store to pick up a Syncra 3.0 at 714gph or 9.8ft head. Perfect! Good flow through the tank and very quiet. Thanks Cuda for buying my 4.0!  The protein skimmer is just starting to make good bubbles, but still has to wait before I'm getting any foam out of it. Tomorrow my live rock is being delivered; so excited!