Rabbut's Diy Skimmer

[rabbut]

OK, here is a skimmer I DIY'ed for my marine tank. Pictures first and then a description of how it works.

Thats the feed into the skimmer from a Maxijet MP1200 powerhead, through a reducer into 22mm pipe in the skimmer reaction chamber

That's the afore mentioned pipe in the skimmer reaction chamber, and the air block from which the bubbles are created to do the skimming

Thats the thing going. Not a lot to be said about this one, other than just out of site there is another pop-bottle as the collection cup.

The thats the rather un-interesting drain back to the main tank...

How it works

Water gets pumped into the skimmer through the central pipe, where water is then forced to flow back down against the raising air bubbles to increase contact time and thus (hepefully) efficiency. The pump it's connected to puches out a decent amount of air, such that, when running, you cannot see into the reaction chamber, except from a couple of cm's gap at the bottom where the air does not quite get to.

As the foam collects it's muck, it raises up the neck of the pop bottle, and into the ridged pipe, where it is forced by the incomming air, through to the collection bottle where it condences into skimmate.

I thought our tap water round here was good quality, but when I did a 3 litre top-up with it, the skimmer collected about 4cm's of very dark skimmate overnight in the pop-bottle. It isn't kicking out much ATM, as there isn't realy anything to remove going into the system. most of whats comming through ATM is just water that presumably is a result of condensation and the like. Unfortunately I cleaned out the collection cup since the top-up, so can't show what it removed, but that would be equivalant to a weeks worth of skimmate on a heavily stocked 50g QT system at work from a Aqua medic Turbofloator jobby...

I have someone enquiring about having one of these built for a 300l tank, and I'm not shure if it can cope. Any thoughts?

Also, surgestions for any improvements would be appreciated

All the best
Rabbut

 

[SkiFletch]

So wait you're injecting air with both an airstone and a maxijet? Should actually handle a decent water volume. My only concern is the collection cup idea... It'd be better if you had the pipe coming off the top of your 2L bottle extend up into another upsideown bottle so the bubbles can go up the pipe, break on the surface and fall down into the upturned 2L bottle. Make sense? Trying to force bubbles through a small pipe is probably not the most efficient way to go.

 

[SkiFletch]

And FYI due to a comment on your other thread; air driven skimmers work very well, the only drawback is that the airstone will need to be changed/cleaned with some frequency as the airstone slowly diminishes in capacity as time goes on. The pump-driven ones are more constant and need less maintenance/replacing. And since we all hate maintenance, that's why they've gained such popularity

 

[rabbut]

Ah...OK, thanks Ski. I though there was a performance thing going on with the air driven ones along side the maintanance, but NM, looks like I was wrong

The air pump is the only source of air into the skimmer, the maxijet just pushes water. I played with the idea of using the MJ for air injection, but figured the bubbles would be too large to be effective by the time they for to the reaction chamber...

It's an interesting surgestion to use a pipe to rig the two bottles together collection cup over reaction chamber as normal. I cannot see how I could do that though, without having the skimmate falling back into the water colum, or having the foam escaping from the collection cup... Any surgestions? Idealy I'm after a big collection cup, such that it only needs emptying when the air block needs replacing. That said, I could modify the pop bottle with air line to rig into another bottle after the foam has condenced

The air pump pushes 150lph I believe, so there is 150lph of air through the connector pipe. When bubbles get that far they must shurely be pushed through quite well? The pipe is angled down-hill slightly also... That said, I'm not exactly an expreienced marine keeper, so don't realy know what is a decent output from a good skimmer

All the best
Rabbut

 

[SkiFletch]

Hummm, Ideally you want the bubbles to come out the top of the pop bottle, break into a bigger container and THEN drain down to a storage container. I have to warn you though, keeeping a BIG container of skimmate can lead to some interesting odors coming out of it regardless how it's setup

 

[rabbut]

Do you think that there would be an advantage big enough to be playing with the collection system then, or better to leave it be?

Thanks Ski

All the best
Rabbut

 

[SkiFletch]

Do you think that there would be an advantage big enough to be playing with the collection system then, or better to leave it be?

Thanks Ski

All the best
Rabbut

Dunno, are you actually getting skimmate in your trap?

 

[rabbut]

Was after the topping up I did, and it seems to be pulling out something rather watery ATM with a green colour. Some form of algea from the tank since it's recieving sunlight mebe? There isn't anything in there to break down into stuff a skimmer pulls out yet though, so asside from when I top up, the skimmer isn't realy pulling much out