DIY Protein Skimmer Advice?

[micaheli]

Because of my aquarium stands height limitations, I have to design my own skimmer to fit my cabinet. I may need to make 2 for enough skimming in my 55gal reef. I designed plans for a skimmer 22" tall with a 17-18 inch skimming tower. It will use an air stone and will be completely made out of PVC (due to cost of clear stuff). I have not played with a commercial skimmer yet and do not 100% understand how they work. I understand that with high pH water, air bubbles attract solid waste and undissolved protiens and they rise to the surface and create a nasty, yucky foam. I understand THAT. However, Something isn't making sense to me. All of the skimmers I have seen have an outlet for waste to exit. With that vent open, wouldn't water just come squirting out from the pressure of the pump? Or does the air pressure from the stone keep the water down. In that case, wouldn't I need a valve on that port to restrict the air-flow?

Also, will 17-18" of skimming tower be enough for a 55gal tank? Can somebody beat this into my head? Thanks!

--Micah

[reefrunner69]

There are many manufatured skimmers that will fit under a conventional 30" aquarium stand, so I think the size your looking to do should be fine.

As for the DIY stuff...I tend to hurt myself when I DIY so I'll just move this to the DIY forum for ya

[dansemacabre]

I can't speak for skimmer on the whole, but I can tell you how mine works. I have a Berlin XL Classic (made by Red Sea, which I got at HUGE discount [$80!!!]) and it's enormous. Anyways, to have enough suction to pull air in through the venturi valve, there's a tapering valve...it goes from (for example) ½" diameter to about an 1/8" in a length of about 3/4". All this water (coming from my MagDrive 9.5, at 950gph) is forced into this tiny opening in a relatively short distance. This pulls air in from the venturi tube. Anyways, because it is so small (guesstimating at about 1/8" as I said) it greatly reduces the flow through the skimmer. So, by the time the water reaches the exit, there's not a ton of water gushing through it, so the two 3/4" exit nozzles are more than enough to handle the flow out of the skimmer, so the only thing making it to the top collection basket is what floats there (the skimmate [that "nasty, yucky foam"]). As far as making one yourself, I haven't done it, but it doesn't seem too hard. If you do a search in the forum, you could probably find past posts. About.com 's saltwater section has a subsection for DIY and in that, DIY skimmers. Oh, and of course justDIY is awesome, and he'll prolly have a lot to help you out with too. If I'm not being clear enough, I can take some pictures of it for you. HTH!