Semi-Closed loop/High Turnover sump idea.

While trying to plan out the sump setup for my 85G tank, I took a look at the stack of equipment I have already and started thinking. I am a huge fan of Closed loop systems, and hate seeing powerheads, and was planning on a closed loop system for my tank. So far I don't have have a pair of smaller return pumps I was planning on using for a simple sump (for redundancy mostly), but i was thinking about how I could in corporate my sump and closed loop into one.

So here is my idea.

• 3 Ten Gallon tanks. One on either side of the stand, and the last one in the middle.
• 3 returns from the DT. 2 small ones on the either side, and 1 larger one on the middle. Each draining to a 10G tank.
• The left side tank would act as a fuge, the right side tank would be used for acclimation, and the middle would be the sump (skimmer, heaters, return pump).
• The fuge and acclimation tanks would have drilled and weired overflow boxes that drain to the sump to maintain a constant water level. (The wiers could be replaced with a baffle near the overflow if necessary.)
• The outer drains would be valved to adjust flow down to desired turnover, and the the center drain would handle the rest of the water return. Since that center drain is basically being returned to just the sump which would house the return pump, it basically makes the system almost closed loop, minus the 1' of pipe directly connecting the drain to the pump.

I understand that the same could be done with a alrge tank, and several drains. I just wanted to use the seperate tanks for the experiment, and to try and explain the fuge and acc. tank as seperate entities from the sump.

 

A closed loop means that the pump takes a suction off the same tank it discharges to. One benefit of closed loops is that there is no head loss because the suction and discharge are connected to the same water level.

What you are suggesting is a open loop because it is open to atmosphere at different levels. By using pumps in such a manner, you have to have your high flow at the expense of head pressure. So say you want 1500gph.... in a closed loop there is no head loss, in your system you will have head loss. It uses a lot more energy to pump all that water up 4 feet to get your tank flow from your return pump.

 

I guess I am not understanding. What advantage are you trying to gain in this design?

M

 

Very true. I knew that by calling it a "Semi-Closed loop" was even a stretch. The reason I had called it that is the association with multiple high volume return nozzles and a general lack of powerheads. If there is a another term for this, I'd prefer to be set straight than look like an idiot. Thank you for bringing up the lack of headloss of a closed-loop system. I had completely forgotten that fact, and was thinking that it shared the same losses as an typical sump pump. I'll certainly re-think the single pump system. But that being said, the use of eductors/penductors could counteract that problem by increasing in tank waterflow without the need to increase sump turnover.

What i'm looking to do with this setup is to create high water turn over in the DT, which in turn requires no use of powerheads, but without overpowering a fuge or acc tank, all while simplifying plumbing by using only 1 pump. I understand that I've basically complicated a simple single tank sump by dividing it into 3 tanks, but it's cheaper and easier for me to drill 3 10 gallon tanks that I already have than buy a 40l. Plus it gives me the flexibility to completely remove just part of the sump from the system if need be.

 

Ya, it's really about power use. Power heads are more efficient that return pumps. Closed loops are more efficient and no equipment. The educators would help you out.

Just think of power consumption in general. Powerheads, return pumps, closed loop pumps all add heat to the system by wasting power. Unless of course you use an external air cooled pump. You still have the power loss, just not all the heat addition. Even worse if you need the heat and have to add a heater. (but better if you have to add a chiller instead. ;D)