Flow question?

[townjas]

I have been thinking. We plumb our tanks with an overflow near the top of the tank, and the returns are also near the top of our tank. Would we get better flow by running the returns down near the bottom of the tank? Would this also help keep better turn-over of the water near the bottom?

It would need to be high enough to keep from blowing sand all over, but is it worth trying?

Has anyone already done this? And what were the results?

Also has anyone had any experience, good or bad, with the Jebao DC series of return pumps?

Jebao DC Series Submersible Return Pump w Controller 12000 | eBay

 

[Global]

The fault I can see here is the returns are at the bottom of the tank, what happens when your power goes out, your tank will drain

all the way down to those returns.

 

[townjas]

Yeah, I would use check valves to prevent that.

 

[Global]

I was wondering that, id be careful with one way check valves, over time they have and can fail, and if that happens, you wont know until its to late.

Maybe some other fellow reefers can shed some more light on this and the check valves?

But your idea does make sense. The only other thing I cold think of is running a small powerhead somewhere hidden in the main tank with one of those bendy duck bills attached going under the rock down low flowing that water up towards the weir. Well its a thought anyways.

 

[Big Wave]

There's a better way to do this than check valves, and it's awesome when done well! By keeping all of the flow down low, the surface stays still as glass so you can easily see thing!

You need an extra tank above your display. It could be as simple as a bucket. The return pump fills this highest tank first, which is drilled with a bulkhead on the bottom for a drain. That drain is regulated with a valve (gate is better than ball, but I've seen this done with ball valves). The high tank's drains run down to the bottom of your display (or up through bulkheads in the bottom). With the pump running, you close the valves until the water level rises in your top tank high enough to stop sucking air. A smooth stream of water then rushes into the bottom of your display. When the pump shuts off, you only need to worry about that top tank draining.

I hope that makes sense. I'm new here. :wave:

 

[Big Wave]

Here, I drew a picture:

This is one of my favorite concepts in reefing, and I can't wait to actually set up one of these myself. You can add a stand pipe or a toilet flapper to the top tank to make a surge device, too! It's also the perfect place to add a refugium since the pods can just slip down into the display without going through a pump.

 

[Fin]

Do not rely on a check valve!!! You will be sorry. They are not reliable, no matter which one you use. They eventually will get dirty, or something can become lodged in them that will prevent them from sealing.

I have been using returns on the bottom for 7 years with no issues. Use a closed loop. This is how I did mine. I use an OceansMotions 4 way valve and a Dart for flow.

I ended up changing the configuration of the returns on the bottom (did not use the Lok-Line) , but I think you can get the idea how it was plumbed. All returns go over the top, but could have just as easily been drilled in the bottom. The lower front returns are pointed at the top of the two overflows in the tank to help direct suspended solids up and out of the tank.

This ended up being what I did for the returns on the bottom front corners.

 

[Big Wave]

Nice plumbing! I love schedule 80.

 

[Fin]

Nice plumbing! I love schedule 80.

Thank you! I don't think the gray pipe and fittings are exactly schedule 80. I ordered that from OceansMotions in Canada when I got the 4Way valve. The pipe and fittings are the same thickness as American Schedule 40. The fittings I have seen in the U.S. for schedule 80 are very thick and the opening is quite a bit narrower than schedule 40. It was mostly the color of it that I was after. Not as noticeable behind my tank from the side as white PVC and it matches the valve, unions and Hayward ball valves.

Also, if you notice, the 1" pipe running down the back wall on both sides of the overflow, is black PVC. One of them is now covered with GSP, but I used black PVC to blend in better with the black background.

 

[townjas]

Those are awesome ideas for a new tank. But mine is up and running

 

[Fin]

Those are awesome ideas for a new tank. But mine is up and running

You can install a closed loop without drilling the tank. A bit more visible plumbing would be involved. You were asking about returning from the bottom, so I think most of us that replied assumed you were planning a new build. It is still possible though.

HOLY MOLEY Gary! That tank looks SWEET!

Thanks!
(Build thread on LARC - GPReefer)

 

[townjas]

Thanks Fin, I may look into doing something like that.
I just set up this tank about 6 weeks ago and was thinking I would like to get more flow down low but my 2 WP-40's blow the sand around too much!

 

[Big Wave]

Have you thought about taking the sand out? :wink:

 

[townjas]

Nope.
And here is why...
I am not a huge fan of bare bottom tanks unless it's a frag tank
I have 2 wrasses and getting at least 1 more
and lastly I reinforced the bottom seals by laying strips of 1/2" glass around the bottom perimeter and applying a lot of silicone. (this was a recommendation from the owner of my LFS) so the bottom of my tank is not pretty.

 

[Daniel@R2R Verified Admin]

Awesome stuff! Fin, got any pics of that tank with coral in it?

 

[Fin]

Awesome stuff! Fin, got any pics of that tank with coral in it?

Well, this thread is not about me, but here is one pic. This was about a year and a half ago. I had some misfortune and it doesn't look like this at the moment, but it is on the way back. You can barely see, but the returns on the bottom are grown over with GSP and anthelia. I hope townjas won't mind the pic in his thread.

 

[townjas]

No I don't mind and nice looking tank!

 

[Fin]

No I don't mind and nice looking tank!

Thank you.

 

[ReeferRookie]

Nice tank gary. And i wondered this myself. With the flow at the bottom setting up a safety valve not.a one way but one you can manually shut down urself. Can this help from flooding ? Just a question

 

[Fin]

Nice tank gary. And i wondered this myself. With the flow at the bottom setting up a safety valve not.a one way but one you can manually shut down urself. Can this help from flooding ? Just a question

Thank you! I guess I am not following you. Do you mean like with holes drilled in the bottom of the tank? If so, I would never do that, unless it was with a closed loop. All water would stay within the loop's plumbing and pump. No need for a valve of any kind, unless it was to control the amount of flow leaving the pump, or to change direction of the flow (like with a 4Way).

In my tank, I drilled a 1½" hole in the back wall and installed a strainer to keep the fish out of it. That drain is plumbed to the input of a Dart pump. The return of the pump runs up to the OceansMotions 4Way (diverter) valve. From that valve, water is diverted to two different outlets at a time. Mine returns bottom left & top right and top left & bottom right. The two upper front returns run from the valve, along the top of my tank and into the water at the upper front corners. The bottom returns leave the valve and go down the back wall, along the bottom of the tank (under the sand), each to a lower front cover.

If the power goes off, the water just stays in the plumbing and pump. No possibility of overflowing the sump or causing a flood.