Close loop pump in overflow of peninsula tank?

[OriginalUserName]

I'm planning out my upgrade and it's looking like I'll be doing a 140g peninsula.

I feel like no matter what power head options I go with flow will be an issue on the far end of the tank. I'm not planning on needing SPS flow on that end as it will probably be mostly be negative space and maybe a small grouping of clams. (SPS will be mid tank and overflow side) I think running a very simple closed loop to supply basic water movement to that end of the tank (routed under rock/sand) would be a good option. Is it a reasonable solution to place the CL pump in the overflow itself? I could drill a bulkhead into the tank to supply it but I'd rather just have an open intake. Just a few hundred gallons an hour to keep water moving back towards the return should help a ton.

My powerhead plan is to run two large gyres mounted vertically on either side of the end return, and possibly a couple MP-40s or Neptune Wavs to supplement. Any thoughts or suggestions would be appreciated.

 

[mcarroll]

Tunze has good options for penninsula tanks, and unless it's a rea-a-a-a-ally long 140g, flow at the far end should not be an issue.

Between the wide selection of pump sizes they offfer, the different pump styles they offer as well as the Tunze Rocks for potentially hiding pumps "out in the tank", you have tons of options, in fact.

Here are some stats that can help you pick, (although it doesn't include pumps made since the list was made such as the 6040 or 6150):

Here are some rough approximations of the flow patterns for our Stream and Nanostream powerheads. The first number is the distance (length) it will reach. The second number is the diameter of the flow towards the end of the stream (keeping in mind the diameter increases the further from the pump you measure). All numbers are in feet.

Nanostream
6015 2 x 1.5
6025 2.5 x 1.5
6045 3 x 1.5
6055 4 x 1.5
6095 3 x 3

Stream 2
6065 4 x 2
6085 5 x 2
6125 4.5-5 x 3
6105 7 x 2 (configured for narrow-flow)
6105 4.5-5 x 3 (configured for wide-flow)
6155 6 x 3
6255 7 x 3.5

 

[OriginalUserName]

Tunze has good options for penninsula tanks, and unless it's a rea-a-a-a-ally long 140g, flow at the far end should not be an issue.

Between the wide selection of pump sizes they offfer, the different pump styles they offer as well as the Tunze Rocks for potentially hiding pumps "out in the tank", you have tons of options, in fact.

Here are some stats that can help you pick, (although it doesn't include pumps made since the list was made such as the 6040 or 6150):

Thanks. I was planning on doing a basic flow test with just powerheads before deciding either way, but that makes me feel better.

I'm looking at the Red Sea Reefer 650. It's "only" 5.25'. Whatever pumps I add I'm planning on running them anti-sync to periodically get the water moving in a circular motion around the tank.

I totally forgot about the "rock" pumps. Good point.

 

[Greybeard]

I have a peninsula style 140, 60 x 30 x 18.

Flow is indeed a challenge.

One problem I experienced that I was not considering... all the pumps on the wall end pushing away kept a layer of scum on the water surface. Pumps kept the water surface from cycling through the overflow, as it should.

I tried many configurations to address this. Gyre pumps, varying types of prop pumps, varying placement and timing. Even borrowed a Tunze 'rock' pump... didn't work out well for me. A basic circular flow pattern seemed the only way to keep from building up surface scum, and to be really effective, it had to be a smooth, constant, laminar flow... not ideal for corals of any sort.

After some time dealing with this, I ended up with a pump on the exposed end of the peninsula. Didn't want to do it, but there just wasn't any other way to achieve decent random flow patterns and effective surface skimming. With some volume of surface agitation pushing back towards the overflows, surface scum is no longer a problem. Flow is still circular in nature, but with some random currents and eddies, based on mismatched pump timing.

A closed loop may well be the 'right' answer for you.

 

[OriginalUserName]

I have a peninsula style 140, 60 x 30 x 18.

Flow is indeed a challenge.

One problem I experienced that I was not considering... all the pumps on the wall end pushing away kept a layer of scum on the water surface. Pumps kept the water surface from cycling through the overflow, as it should.

I tried many configurations to address this. Gyre pumps, varying types of prop pumps, varying placement and timing. Even borrowed a Tunze 'rock' pump... didn't work out well for me. A basic circular flow pattern seemed the only way to keep from building up surface scum, and to be really effective, it had to be a smooth, constant, laminar flow... not ideal for corals of any sort.

After some time dealing with this, I ended up with a pump on the exposed end of the peninsula. Didn't want to do it, but there just wasn't any other way to achieve decent random flow patterns and effective surface skimming. With some volume of surface agitation pushing back towards the overflows, surface scum is no longer a problem. Flow is still circular in nature, but with some random currents and eddies, based on mismatched pump timing.

A closed loop may well be the 'right' answer for you.

I'm thinking it might be tricky to avoid that even with a closed loop. Perhaps the return very close to the far end pushing water straight up towards the surface...

If I was going with a rimmed tank I could somewhat hide something on the far end and just route the cable around the lip, but rimless really prevents that.

 

[Greybeard]

If I was going with a rimmed tank I could somewhat hide something on the far end and just route the cable around the lip, but rimless really prevents that.

Yup, makes it harder. Here's my solution

Shot was taken early on in the process. The cable tie mounts are superglued to the edge glass. Secure, and as unobtrusive as I can make them.

I tried an MP60 there, didn't work out for me. 1st, they're NOISY! The whine these pumps produce is annoying to me. 2nd, you can't aim the flow. I need a good deal of surface agitation from this pump. In order to achieve the flow I needed with the MP60, I had to put the pump so high it was sucking air from the surface.

 

[mcarroll]

Folks are too focused on "gyres"....I think because it's a novel word.

Focus on "tidal flow" instead.....flow in one direction for hours, followed by flow in the other direction for hours. Resistant to buildups, and dead zones. (Each tide can be made to have a gyre if it helps. )

 

[OriginalUserName]

Folks are too focused on "gyres"....I think because it's a novel word.

Focus on "tidal flow" instead.....flow in one direction for hours, followed by flow in the other direction for hours. Resistant to buildups, and dead zones. (Each tide can be made to have a gyre if it helps. )

FWIW I like the gyre pumps because of the wide flow, the actual gyre movement is a secondary concern really. I have the Icecap 1k (set to alternate) on my 29 cube, with a Jeabaeo Sw-2 (on random) and a koralia 425. Between the 3 the entire tank has constant water movement.

Yup, makes it harder. Here's my solution



Shot was taken early on in the process. The cable tie mounts are superglued to the edge glass. Secure, and as unobtrusive as I can make them.

I tried an MP60 there, didn't work out for me. 1st, they're NOISY! The whine these pumps produce is annoying to me. 2nd, you can't aim the flow. I need a good deal of surface agitation from this pump. In order to achieve the flow I needed with the MP60, I had to put the pump so high it was sucking air from the surface.

Not bad. I can't stand noise myself so I probably won't go that route either. I wonder if I could add a slim strip painted to match the stand to cover the cord entirely.