protein skimmer size

[Sleek07470]

I know the setup and workings of a protein skimmer, but i'm not sure just how big a skimmer is needed for a cretain sized tank. I'm going to be working on a skimmer for a 30 gal. and was just wondering how big a skimmer would be needed and just how much size matters.

Thanks!

 

[Diablo]

I've done a bit of reverse engineering of some of the curves published in Escobal's book on aquarium engineering.

If V is the volume of your tank in Gal(US), then:

The amount of water you should move through your skimmer per hour is 3/4 x V.
In your case, this is 22.5 gal.

The diameter of your skimmer should be at least: D = sqrt(V/5.25)

In your case, your skimmer should be at least 2.5 inches.

Always build your skimmer as tall as possible. 4' - 5' is preferable.

For a tank this size, I would probably build a counter-current air-stone skimmer, but any design that meets these minimum requirments will do.

Cheers

 

[rabagley]

These numbers are highly dependent on skimmer design and seem appropriate to countercurrent designs. The Aqua-C line doesn't have anything close to those numbers (except in GPH, which is about right) but are widely acknowledged as very effective skimmers.

Regards,
Ross

 

[Diablo]

With respect, and not wanting to get into a debate, the AquaCs are not that different to these figures:

For example, the EV-240 is 6"OD (versus 6.76" according to equations) and a total reaction height of >20".

Height is really the only big difference. The height of the skimmer affects the % of crap skimmed out. For example, (and not based on any real numbers), a 2' skimmer may skim out 70% of surface acting proteins, while a 4' skimmer might skim out 90% of surface acting proteins.

The air/water injection technique can never compensate for lack of contact time. If I had the room, I would always build a > 4' skimmer... if not, then I would settle for a > 2' skimmer.

 

[Anonymous]

Another potential point of debate in this is wet skimmate vs. dry...