Questions about this DIY skimmer design!

Ok, so I've spent about the last three hours looking around at DIY skimmers and the sort. It seems that counter-current skimmers do the best job from what I can tell because of independent adjustment of the air going in the skimmer and the water flow rate.

According to this guy's website (who appears to be fairly knowledgeable) you should have a flow-rate in your skimmer of y=3/4x where x is the number of gallons of your fish tank. So for my 29 gallon tank that is 21.75 gph for optimum efficiency. Also, I should be using 3" PVC for the skimmer, and it says bigger is better. So I suppose this would work out to be 4 or 5 feet tall on the outside of my tank with return.

I also figure I'd be using a ball valve on the intake and outtake of the skimmer. This is where I get confused as his diagram is rather basic. Here is the website: Snailman's DIY 3" Skimmer.

I think my confusion comes from how the water gets out of and returns to the tank with a pump. Also, I've seen some DIY skimmer articles saying you could use something as basic as a powerhead, but I assume that would only be applicable for in-tank installation, which I don't want. At any rate, I've gone into photoshop and modified his diagram to one that shows where I'm at with this DIY project. I'm attaching that file. I also think I'd like to build a separate waste collection cup like he has on his website.

In short:

What should I use to get the water in/out of the skimmer?
Where do sections K&R fit into the equation?
How can I figure out how to adjust flow to 21.75 gph?

I understand that K is water in and so the pump will somehow possibly be installed in between there and the aquarium, and that R is possibly the return back to the aquarium. As I understand it that additional section that goes 2"-4" into the aquarium is for anti-siphoning? I'm confused about all that and need clarification!

And any additional suggestions/comments are welcome and greatly appreciated!

Thanks guys,

Drew

 

k is the inlet from your pump . r is just for draining the skimmer for cleaning or dismantleing ... ive always wanted to diy a skimmer and i think im going to for my big project tank and i dont see anything how to adjust the flow or bubble height oh i get it section p is for setting the water height in the skimmer beems like that would be tricky to adjust if you put a gate valve in that spot it would work easyer

the height of the skimmer increases dwell time ( how long it takes for that bubble to make it to the top wile hopefully bringing skinmate with it ) alot of ventury designed skimmers use a bubble plate for that purpose but in this case the air is getting introduced via an air pump

you can use a standard power head to run this setup i would probly use a 1200 maxijet it would work as he designed i would more than likely go with 6 inch diamiter if you can find it 3-4 foot tall it would probly be verry efficiant your going to need a good air pump and i would get one with dual ports and gang them together with a tee and a 3 inch minimum or larger wood airstone so you get a good amount of bubbles increaseing your chance of sucsess . the wood airstone is key as it will make finer bubbles do to haveing smaller pores for the air to excape idealy when you look down the tube you want the water in there to look like milk and set it up where you can change out the stones after a wile thay start to deteriate and the skimmer will lose its efectiveness

with any luck this all makes sence to you

oh and 'h' there should be a hole on top i would seay 3/16 of an inch so that air can come in there preventing a siphon so that the skimmer wont overflow when the power is shut off

 

Thanks for the reply, after looking at it awhile longer I figured the bottom part was to clean it out. Good to know I can attach a hose to a powerhead and run it off of that, and I'm probably gonna get the Tetra-Luft pump's the guy was talking about with 3x wooden air stones. I'm making it out of 3" PVC because the graph he has from a DIY aquarium book recommends that for a 29 gallon tank.

I'll let you know if it works out well, I'm headed to Home Depot to buy all the stuff I need!

 

I would not really say counter currents are the best. It's a dated design. Easy to make though. Seems lots of folks DIY beckett skimmers. Seems to be easy to build. I think a Beckett would be a bit big for your 29g. They use lots of pump for what they do. They seem to have a fan base on larger tanks cause they have large air draws and can process a lot of water.

CC seem to be easier to DIY out of PVC. Needle wheel skimmers work best, but harder to make. You can use cylinder acrylic... but bubble plates are not just plastic with holes in it. They are actually hard to make work well. I know some other guys that do a lot of DIY stuff. If you have the space and the time seems like your project is worth while. Keep us posted how it turns out.