Deep sand bed connected to Undergravel filter

[Chandra Mohan]

HI guys, need your expert comments on this filteration system.

Please see the attached file

DSB cum UGF.ppt

[xaine]

Depending on the size of the sand you use for your main tank, the UGF might get choked in due time.

The powerhead might not be powerful enough to suck up detritus from the far end, hence that would not be built up over time

And most would avoid using UGF-style as it tends to be a timebomb for a tank crash.

I have used this on my FW setup before, and you can be shocked to see the amount of gunk left lying when I decommed it.

[bluemask]

UGF is a big no-no...it simply suck waste underneath & waiting to become a toxic ground.

[tunicate]

Looks like your DSB is in an air tight sealed tank in order to push water back up into main display. In that case, you'll be running it like a huge canister filter filled with sand. You might want to setup a small prototype to test its effectiveness.

[huntingforfish]

agree that ufg could become clogged in the long term, generally not used in saltwater tanks anymore. Why must connect a ufg to a dsb though? U could just connect a remote dsb straight to tank, lots of threads online on building one.

[Marcuss]

Just to share some of my experience here,

Under gravel filter still very good filter due to the sand surface for bacteria colonization are very large and simplicity to operate but you need to follow few simple strict rules listed below,

1. The sand particle size must in between 3 to 5mm (smaller size the sand bed will clog faster and too big you need to create more thicker sand bed)

2. Thickness must in between min 1 to 1.5 inch max

3. Need to vacuum the sand bed every water change, so make sure your tank are at lease 2 ft, if not you will run out of water before finish vacuum the sandbed.

4. Every weekly water change Must add gravel cleaner bacteria supplement.

5. Pump connected to he under gravel filter must be strong or else you will having a stagnant water somewhere in the tank bottom sand and that will create hydrogen sulfate pocket.

This type filter most practical if using it in the fish only tank because if you keep coral and you will add a lot live rock that will make the tank vacuum more difficult.

[Marcuss]

Something wrong with your tank circulation design, the power head should place at the return side and you also will encounter main tank overflow if your sand bed clog due to the water from your sump return back to your main tank VERY DANGEROUS!!!!