Using underflow.. Any ideas how best to incorporate shallow sandbed?

[kaykay]

Hi,

I've recently bought a 2'x1.5'x1.5' tank that comes with ios at the back portion of the tank ie usable display tank is 2'x1'x1.5'(H). Display water volume should be about 80 liters.

The outflow to the ios has both underflow and surface flow.

The underflow portion has a piece of acrylic teeth covering it.

Height of the teeth is 1.5", spanning a width of about 8". (hope you guys understand the description)

However, I want to keep some gobies. As such, I want to lay some sandbed, roughly about 1" thick.

Any reefers has any experience with such a setup?

Will sand clog up the underflow teeth?

Idea..

If i stick an L-shape piece of acrylic around the underflow area, will the underflow current be compromised?

How far from the underflow should such a piece of acrylic be for current to be effective?

How tall should the acrylic piece be?

Will there be a deadzone where this acrylic enclosure is?

I'm prob using an Eheim 1250 (1200l/hr) for the return, tee-ing to 2 PVC elbows in the display. First one at 2" above sandbed, and the other at 12" above sandbed.

Advice is kindly appreciated.

Thanks.

[kaykay]

Note. This piece of acrylic is to block sand from clogging, or entering the underflow chamber.

[tunicate]

If you're having sand, just block off the underflow to disable it. The rest should work as normal.

[kaykay]

I'm just greedy.

Thinking of the best of both worlds, underflow with sandbed.. Lol.. Wonder if there can be anyway they can co-exist?

[xaine]

Sand would choke the underflow in time to come unless you use coarser grains. But it will be a maintenance headache anyway. The design of underflow are best kept with bare bottom.

(null)

[kaykay]

How about my idea of the L-shape piece of standing acrylic, 5 cm tall, to surround the underflow.

This will block sand from clogging the underflow.

Will it work?

[tunicate]

If the vertical piece blocking the sand protrudes more than 6 inches over the sand bed, it may work. This is because of water movement, critters, fishes, as well as people disturbing the sand bed.

[kaykay]

Thanks for the advice.

All points noted.

When tank is setup with the L-shaped acrylic blocking the underflow from the sandbed, I'll post reviews here.

[Jameshong]

If your underflow clogged, it's still have overflow to take care of the water to IOS so I dun see there is a problem leh.. !

[kaykay]

I am thinking of this. Think it'll work?

[kaykay]

The acrylic fence is 5cm tall. Only intending to use a shallow sand bed of 2-3cm.

Not wanting too much sand turbulence, I'll be using bigger sand particles.

[ReDDeviLs]

over time, dirt and other loose stuffs like nori will accumulate there and rot which contributes to water pollution.

best is if you can access to it so you can keep it clean when you need to.

[kaykay]

Yup fully understood

I just filled the tank with water and turned on the 1250 return. There were some loose dirt in the pump, causing a small suspension.

I was observing the turbulence within the tank. There were indeed some dead spots, definitely needs at least a small powerhead or two.

Also observed that the underflow took more volume than the surface flow. So at least I don't have to worry about the volume within the small fence.