Plumbing a Nu-Clear Canister Filter

[tvigneux]

Hello, I have been out of the hobby for a few years and have decided to return with a new 180g acrylic tank. This is my post post on the forum. The tank is plumbed with an overflow in the back center with holes drilled for 1" bulkheads. I plan on filtering the tank with an Eheim Pro 3 and a series of Nu-Clear canister filters (2 mechanical, 1 chemical and 1 biological). The Nu-Clear canisters will be fed in series by a Quiet One pump.

I plan on using the overflow to provide the input to the Nu-Clear canisters. However, I am concerned about the pump cavating. One thought is to drill 2 holes into the side of the overflow to flood the chamber. Another thought is to use a standpipe to raise the raise the water level in the sump, but I am not sure if this will do any more than quiet the overflow? A final option would be to use a sump....

Any suggestions or advice is greatly appreciated.

Thanks,
Todd

 

[tvigneux]

To add a little more detail about my planned setup. The overflow is plumbed with 3x 1" bulkheads, which I understand to be rated with a flow rate of 600 gph. The overflow will feed a Lifeguard Quiet One 6000 pump which is rated at 1070 gph at a 6' head. I also will be using a Eheim Pro 3 canister. The plan is to feed the Quiet One with 1 of the bulkheads, use the 2nd bulkhead for the return from the Quiet One, and the 3rd bulkhead to feed one of the two inputs on the Eheim with the 2nd input to the Eheim coming from the back of the tank.

Will I have any issues with flow balance or anything else of concern?

Thanks

 

[the_deeb]

Your plan sounds fine to me. A few things to consider though:

What flow rate is your overflow rated for (not the bulkheads, but the overflow box itself)? You need to make sure that the overflow rate can keep up with the flow rates from your pumps, otherwise the pumps will drain the overflow box and run dry. You could easily solve this by cutting some teeth out of the overflow, or drilling some holes in the chamber as you mentioned.

I'm pretty sure the 600GPH rating applies to a gravity fed bulkhead in a standard overflow. In your case, it's going to be operating at full siphon, which can be a lot faster (probably over 1000GPH).

Is the Quiet One pump pressure rated? You really need to use a pressure rated pump to run the Nu-Clear canisters, especially if you're going to have several in a series. I'm currently using a Velocity T3 to feed my pair of Nu-Clears and it works quite well.

Are you going to hard plumb the canisters with PVC pipe or use tubing? Hard plumbing looks nice and clean, but I personally find tubing to be a lot easier and more convenient to set up. If you do decide to use tubing, remember that good quality hose barbs can reduce the size of the fitting quite considerably, so consider scaling up the size of your plumbing after the bulkhead and then scaling back down to 1" to fit the Nu-Clear input. This should minimize any concerns about pump cavitation.

If I'm reading your plan correctly, your intake and return are from adjacent bulkheads within your overflow. This is probably obvious, but be sure to include internal plumbing on the return line to deliver the water back to the tank outside of the overlow so that your intake isn't redrawing too much of the returned flow. Consider plumbing some of your returns to provide flow near the bottom of the tank to help lift debris off the bottom and into the water column so that it can be picked up by the skimming action of the overflow.

Hope that helps.

 

[tvigneux]

Thank you for the information. I have modified my design since the initial posting and have added a 29g sump to the set-up. I am using 1" ID flex tubing between the canisters; 2x 1" bulkheads reduced to 3/4" ID to drain the overflow into the sump; and 1x 1" bulkhead reduced to 3/4" ID return to the tank. The return line does come up into the overflow, but is plumbed to return to the main tank through 2 holes in the top of the overflow.

I do not know if the Quiet One is pressure rated?? It is submersible and I am a bit worried that if it does not have sufficient pressure to run the canisters, I may not have enough room in the cabinet to add an external pressure pump without changing the placement of the canisters.

As some parts of my plumbing are PVC with PVC cement, I have allowed the glue to cure for several days and plan to fill the tank tonight or tomorrow morning to test the flow rates. Hopefully I won't need to drain the tank and revisit the plumbing.

Thanks again for your help.