Closed loop intake??

[ac green]

Tried to post this similar thread on the main board but got few responses, so let me have a try here.

I am in the design phase of a new rimless tank and wanted to try and go with only a closed loop on an oceans motions and a return pump for flow, I would like to try and getaway with no extra pumps if possible.

So my question is in regards to the intake of the CL, I was thinking of two options

1) In the bottom of the overflow box itself. I would prefer this option but see a problem with the possibility of the overflow not being able to handle all of the water or overtime the teeth of the overflow getting clogged with corraline and algae which eventually would slow down the overflow and may cause the tank from overflowing. I guess if the teeth is preventing the flow, the other option would be to go with an overflow with no teeth and have th water simply overflow into the prefilter. I should also note that one of my plans was to have the overflow the entire width of the tank with a false back and the drain to the sump and CL would be 1.5"

2) In the bottom of the main display itself with one of those huge strainers. Less preferred but

I have never personally setup a CL, so any previous experiences or gotcha's would be much appreciated.

tia
ac

 

[sid700]

I thought about doing #1, but decided against it .

I just eliminated the overflow and stuck the intake in the tank, 4 inches below the waterline and hid it behind some rocks but still accessible. Even if the strainer gets a little clogged, the intake through the pump will still equal the output.

I asked myself the following:<ul>
If the return pump fails, would the CL pump still have water to pump?

Would CL output act as drains to the overflow and into the sump if the power goes out?
</ul>
I figure not going through the overflow box was one less thing to worry about.

 

[reefboy1]

AC,

I would advise against putting the intake in the overflow box. The weir size will definitely limit the capacity (with teeth or no). Safer to do it in the main tank.

I have a 2" intake for my OM 4-way. You're welcome to come over and have a look at how I set it up.

Art

 

[ac green]

Thanks art and sid for the replies.

Guess I will go against the intake being placed in the overflow, as it would be one more worry.

Art- I will definetly take you up on that invite to come take a look at the setup.

 

[arthurlo]

With respect to having a big strainer near the bottom of the tank, just make sure that it is well above the substrate. Sometimes, the intake may suck in enough substrate that the pump may jam up.

As Sid mentioned, having the CL intake a few inches below the intake for the overflow would work well.

 

[ac green]

Good point athurlo. Still debating if I want to go with a remote DSB or a SSB in the tank.

 

[Kinetic]

hey aaron, I had been designing a CL for my other tanks for some time.

the overflow isn't going to handle flow you'd want, unless the overflow is massive. Also, if you have an OM closing and opening different # of outlets (meaning not a constantly flow) your overflow will be noisy, and your drain (stockman or other standpipes) will also be noisy.

For my closed loop, I opted for 2 intakes, mainly because anything smaller than a tang would be at risk of getting stuck in it. Also two for redundancy.

One intake design I would highly recommend would be two intake holes, attached to a "spray bar" intake. If you run this with black PVC, behind the rockwork, it will even out the suction into the closed loop pump.

goodluck!

 

[bingsf]

Hey ac green, did you ever decide on your setup? I am looking to do the same thing with a full width external overflow with the closed loop intake inside the overflow. I calculated that the overflow would be wide enough to handle the flow for both sump and CL but was concerned with the following:

1) 1500gph CL intake would compete with 300gph sump drain and suck water level down below durso intake

2) possible overflow situation if overflow ever clogged - CL will pump remaining water from overflow to main tank

3) CL diverting surface skim from sump drain and back into tank instead

I have an OM 4-way and found the following on their forum:

http://www.oceansmotions.com/forum/viewtopic.php?t=10&view=next

This guy has an external overflow but has a bunch of holes drilled in the back of the tank to allow the CL to intake water from below the overflow. This seems like it would eliminate most of the potential issues and still allow a nice clean look inside the tank. I am considering doing something similar.

Thoughts?

 

[bingsf]

oh, and I am going to use an acrylic tank so drilling should be simple. I suppose this would not really be an option with glass.

 

[Solitaryensis]

Hey Aaron,
Good luck on the new setup, BUT, are you planning on selling the old one
Theo

 

[ac green]

I will be selling the 36x36x18 cube in the garage. The room divider is going to stay up.

Yea, the planning, designing, and setup is what I enjoy most. Going to take my time on this one and try to do it right the first time (if there is such a thing).