Improving flow inside tank

[mindstate]

So I have an 8ft tank with sump where I did the plumbing myself and have 2 outflows (shown in blue below). The flow in the tank is decent but stagnates halfway on the return to the overflow. What can I change or add (like a flow pump or wavemaker) to pull the debris that settles on the ground up to the overflow and how to determine size?

Below is a sketch of the situation, the green line is the flow I'm happy with and where the sand is clean, starting from the orange line I notice debris settling instead of flowing to the overflow and the red line is barely no flow at all.



I'd like to add something like a powerhead or wavemaker, but not sure how to select the correct one, where to place it and how to determine capacity.

Any advice is appreciated!

 

[duanes]

Pump Angle: The Right Powerhead for the Right Flow, Used the Right Way – BRStv Investigates Flow.
I know this is designed for reefers, but lots of goodf info here

 

[mindstate]

Pump Angle: The Right Powerhead for the Right Flow, Used the Right Way – BRStv Investigates Flow.
I know this is designed for reefers, but lots of goodf info here

Thanks Duanes, thats part of my evening sorted.

 

[Backfromthedead]

I would try a couple things first before adding a wavemaker--you may nkt need them.

What i would try is crisscross the return nozzles towards the center of the tank, the one on the right shooting towards the bottom left corner, and the left one pointed sorta midway up towards the right side of the tank. This might not work unless you have some respectable flow through the returns, but it should create some random flow that will whip up the sediment throughout the bottom of the tank.

 

[mindstate]

I would try a couple things first before adding a wavemaker--you may nkt need them.

What i would try is crisscross the return nozzles towards the center of the tank, the one on the right shooting towards the bottom left corner, and the left one pointed sorta midway up towards the right side of the tank. This might not work unless you have some respectable flow through the returns, but it should create some random flow that will whip up the sediment throughout the bottom of the tank.

They are hard plumbed at the moment up to being horizontal to the water line, I could exchange the 90 degree elbow and play around with it for a bit. The outlets are 25 mm (1") at the moment and both pointed in the same directly and slightly tilted towards the surface in comparison to my sketch.

Regarding the pump its a Jecod DCP 8500 (2250 gallon per hour) connected to 32mm (1-1/4") pvc . Tank is 320 gallon.

 

[Backfromthedead]

They are hard plumbed at the moment up to being horizontal to the water line, I could exchange the 90 degree elbow and play around with it for a bit. The outlets are 25 mm (1") at the moment and both pointed in the same directly and slightly tilted towards the surface in comparison to my sketch.

Regarding the pump its a Jecod DCP 8500 (2250 gallon per hour) connected to 32mm (1-1/4") pvc . Tank is 320 gallon.

I see, IMHO that return pump alone will not provide enough flow through two nozzles in that tank to eliminate all your dead zones in that tank, even on full power. So the wave maker or maybe even a gyre pump might be necessary to do what you want. If you wanted to do this with just the return pumps you would probably need to reconfigure the overflow, sump, and pumps for considerably more flow.

My revised idea would be to pick up a gyre pump, just play with location and settings till you're satisfied. Even the budget gyre pumps move a ton of water.

 

[esoxlucius]

Bear this in mind. The flow rates of these products are based on an empty tank scenario when tested in the manufacturers labs. They have fancy computers that track flow and then on the box it may state they do this, that or the other.

But our aquariums aren't empty, they've usually got flow restricting decor in, some tanks way more than others.

My experience with both pumps, power heads and wavemakers is that the figures on the box may look ample and you may think that you've chosen a great product.

Then when you get it in your tank you always end up wishing you'd maybe gone for the next model up, or maybe higher, probably because of flow restriction in your tank as mentioned above.

For this reason I will not buy single speed products anymore, I always go for variable speed now. A bit more pricey maybe but well worth it in my opinion.

And that added feature will mean that, after a bit of tinkering, you will find that perfect sweet spot for your set up.

 

[mindstate]

Bear this in mind. The flow rates of these products are based on an empty tank scenario when tested in the manufacturers labs. They have fancy computers that track flow and then on the box it may state they do this, that or the other.

But our aquariums aren't empty, they've usually got flow restricting decor in, some tanks way more than others.

My experience with both pumps, power heads and wavemakers is that the figures on the box may look ample and you may think that you've chosen a great product.

Then when you get it in your tank you always end up wishing you'd maybe gone for the next model up, or maybe higher, probably because of flow restriction in your tank as mentioned above.

For this reason I will not buy single speed products anymore, I always go for variable speed now. A bit more pricey maybe but well worth it in my opinion.

And that added feature will mean that, after a bit of tinkering, you will find that perfect sweet spot for your set up.

Thanks for your advise. The return pump is variable and I do got a sweet spot for flow through the sump and an equilibrium with the overflow to have basically no noise at all. Which it is perfect for that you can adjust it per 100 l/h. I would definitely do the same for a powerhead.

My revised idea would be to pick up a gyre pump, just play with location and settings till you're satisfied. Even the budget gyre pumps move a ton of water.

Damn, those are 300 EUR+ for a bit of capacity. What is the difference between that and say for example a Jecod SOW30 or SLW30?

 

[Backfromthedead]

Thanks for your advise. The return pump is variable and I do got a sweet spot for flow through the sump and an equilibrium with the overflow to have basically no noise at all. Which it is perfect for that you can adjust it per 100 l/h. I would definitely do the same for a powerhead.


Damn, those are 300 EUR+ for a bit of capacity. What is the difference between that and say for example a Jecod SOW30 or SLW30?

Not sure, possibly one has a controller or bluetooth control option. I use a jebao/jecod scp-150 in my 400g stock tank...think it cost me $120 US. Definitely not a fancy unit but I just leave it on stream flow in my tank so I don't need to mess with the settings.

Ill probably never buy a small circular type wavemaker again. The gyres have sturdier mounting magnets, just as quiet, and even though they are bigger they are less obtrusive imo, probably barely noticeable if you were to orient it vertically in the far right back corner of your tank. They just seem to move much more water as well.