Peninsula Overflow Questions

[aquaticeye]

I am seeing that some of the tanks for sale as well as the custom tank builds available (IE: Glass Cages) have peninsula style overflow and returns (drain and returns all on the short end of the tank).

For those that have experience with these types of overflows, just wanted to check on experience with flow, dead spots, etc...

I have only had experience with setups with back of the tank (long side) overflows with returns on either side of the back (long side again)

Pros, cons, or doesn't really matter it all works well enough?

Attaching photos from tanks from other MFK members

 

[duanes]

I always drill tanks to overflow on one end, so I can return water from the sump on the other end..
One of my reasons is that I keep riverine fish, and want to simulate that kind of laminar flow environment throughout the length of the tank.

On the 6 ft tank above, water from the sump cascades in on the west end, and runs the length os the tank toward the overflows on the east end, below.

In that way on the west end there is countercurrent zone, where rheophillic species thrive, and as it runs the length, gradually chills out somewhat allowing for a calmer zone on the east end, for those fish that need a more relaxed environment.
I also feed on the turbid end, allowing food travel the entire length of tank, providing more opportunity for slower feeders a chance.

One other interesting aspect, I find the countercurrent zone seems to be a place where mulm collects, and concentrates, so is easily seen. So I mostly vacuum there, instead of needing to plow a siphon all over the tank

 

[aquaticeye]

Love the layout for this river type set up

One of the things I want to add is that drain and return are both on ONE SIDE of the short end in the tanks that I'm describing. The picture with the black overflow shows this a bit (the central 3 are the drains, the side two are the returns)

 

[jjohnwm]

It's usually possible to attach extensions to the returns right where they project through the wall into the tank. These extensions can reach anywhere, even all the way across the length of the tank to create an excellent cross-tank flow. Depending upon decor, they can run along the surface...sometimes even completely above water level...or can be run down and then across the bottom, using elbows and other fittings. Again, whether or not this works for you would depend largely upon cosmetics.

I've done this many times with HOB filters, except on those you are extending the intake across the tank from the filter. But it's also worked very well for me a few times when the return is being extended as described.

 

[wednesday13]

Not a fan of the pictured style overflow boxes… i just run bulkheads with assorted screens. I am a big fan of the peninsula style setup tho. IMO its the best way to avoid dead spots as you can easily create a whirl pool effect with 1 return alone. It eliminates the need for any additional power heads and if u position ur return at the water level theres no need for added aeration either. Its the most efficient setup for me as it uses the least amt of equipment to run. 2 returns defeats the purpose. U can always just turn one into a drain tho if they come pre fabbed with 2.
Heres my 450 gal. 8’x3’x32”… been running for 10+ yrs like this un touched with only a mag18 lol… Its current inhabitant lets out human sized dumps and its always clear. Tried to capture the turbulance for ya as best i could. With the correct size and placed return nozzle u can move a ton of water even with an underrated pump to most peoples standards. This is only 4x turnover per hr.

 

[Dégatdeau]

I'm a big fan of my peninsula setup. I only have the return pump, no wavemakers and there is no deadspots in the tank.

It's my first tank with a sump and if I was to do it again, I'd save the money and I wouldn't go with an overflox box. I'd do bulkheads and strainers like wednesday13 has done. I'd go with a smaller pump as well. I didn't think this setup would be so good.

I arranged a pickup tube about 6" from the bottom in one of the bulkheads to the overflox box and the other skims the surface.

 

[duanes]

For me, its all about recreating (as closely as I can) the habitat the species live in , in nature.
Providing the exercise they need.
I must admit, it has never made much sense to me, having both the outflow and return on the same end,
In essence then, the need to put a wave maker on the other end to eliminate a dead end would be a "must".
I usually add a wave maker to help push water along the 6 ft length, but that's because the fish I keep are rheophiiic species that require a strong current and highly aerobic conditions, (not simply for elimination of dead spots) as opposed to conditions for slack water species.
The type species of fish kept, has a lot to do with flow conditions in a tank.
Below is the wave maker, in addition to the 1500 gph pump recycling thru the sump.

Below is the flow of the type river where I collect my tanks rheophillic species, so you can see the reasoning behind my excess flow needs.



And as you can see below, none of the fish I keep, shy away from the strong current.

In fact some areas where I collect make the current in my tank, downright wimpy.

In the area above and below, I couldn't cast the net without bringing up a pleco or 2.

I believe many aquarists vastly underestimate the constant flow many fish experience in nature, and may be why the hormones these fish develop to cope with that flow , are then converted into aggression (especially with certain cichlids).

 

[Backfromthedead]

Ive had good results playing with different peninsula layouts. Much more versatile than standard "back" panel manifold. As an alternative to arranging them in the peninsula layout, you can turn the tank long side against the wall and have easy access to your plumbing or side-mounted sump.

 

[born2lovefish]

My 8x4x2’ is a peninsula style that I had built. I run a Jebao wavemaker about 8-12” from the bottom on the opposite end of the drains that helps create a circular flow in the tank. Works great for stingrays.

 

[aquaticeye]

Not a fan of the pictured style overflow boxes… i just run bulkheads with assorted screens. I am a big fan of the peninsula style setup tho. IMO its the best way to avoid dead spots as you can easily create a whirl pool effect with 1 return alone. It eliminates the need for any additional power heads and if u position ur return at the water level theres no need for added aeration either. Its the most efficient setup for me as it uses the least amt of equipment to run. 2 returns defeats the purpose. U can always just turn one into a drain tho if they come pre fabbed with 2.
Heres my 450 gal. 8’x3’x32”… been running for 10+ yrs like this un touched with only a mag18 lol… Its current inhabitant lets out human sized dumps and its always clear. Tried to capture the turbulance for ya as best i could. With the correct size and placed return nozzle u can move a ton of water even with an underrated pump to most peoples standards. This is only 4x turnover per hr.

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Yes love this. Exactly what I was hoping to see. Thank you