Huh - go figure - I had figured that all multiple pump skimmer designs were recirculation style. I.e, the pump draws water from the skimmer body and the water feed to the skimmer itself is independent of the needlewheel (meshwheel now) pumps.

I had to mod my ASM to be recirculation, basically all I did was drill a new 1.75" hole (the 1" uniseal requires a 1.75" hole same as for a 1" bulkhead) and hooked the pump in that way. For the last year I've been feeding the skimmer via a T off the overflows, now I'm feeding with a maxijet 600 (after trying a maxijet 1200 for the last week). I read on asmskimmer.com/octopusskimmer.com that for a recirc skimmer you want a feed pump about 1.5 times your tank volume (but I'm not sure if that number is just a WAG on their part - I don't know if there are any metrics applied to generate that factor value of 1.5).

Seems to me you might need to think about modding the skimmer itself. The problem is that the pumps are just pushing too much volume of the air/water mixture for the exit pipe to carry out fast enough. You could start by trying to raise the skimmer so that there is a larger height differential, but it sounds to me if you're racing water through the skimmer that it doesn't have a lot of contact time. So going towards a recirc mod on your skimmer might be something to look at.

I'm not sure what I'd do. Bear in mind this is all black magic to me, so don't just follow MY advice because I'm clueless!! :lol:

control air
 

jason
try to control the amount of air entering the venturi with a small valve and it should decrease the bubble level. as the pump breaks in more, increase the air flow to raise the bubble level.

It's actually already started to settle down and I got 2" of stuff in the first 24 hours. It's definitely not as dark as the old stuff but it used to take a week to make what the mod has done in 24 hours. So far I'm happy and look forward to seeing the long term effects of this. The water line is still almost right to the top but the skimmate is thicker and darker now than the wet bubbles that it started pumping out first.

This is exactly my results - in fact it can pull out more in 24 hours than it used to make in a week. But the skimmate is definitely lighter. I used to pull out "Coca-cola black" skimmate, now it's more like "green tea".

But I wonder if it's not unreasonable to expect a lighter skimmate than before, if you're pulling it out faster maybe there's less DOC to pull out?

Because that my airflow hasn't increased and it doesn't appear to be a more voluminous (is that a word?) foam (like what others are claiming on RC), I'm reluctant to try lowering my water level (by opening the gate valve) too much because I'm afraid it will hit a threshold and basically stop producing skimmate. I'm still planning on modding the venturi and maybe the volute to see if I can pull the air volume #'s up a tiny bit.

For me I think the color and thickness of the skimmate has to do with the water level in my skimmer. When I only had one pump running at one time and the water level in the skimmer would fill the reaction chamber, there was a nice thick foam that formed on the top. The fact that the color is weaker only makes me think that given a longer skimmer neck the foam would be thicker but that still doesn't mean that it's not pulling out the same amount of crud with wetter foam. It just overflows sooner and doesn't have a chance to form that thick foam. I can't see this being a downfall but I could be wrong.

Well, it's been four days and the collection cup is full of dark skimmate. I was expecting the skimmate to be clearer but it's still pretty dark. Not quite as dark as before but almost. I'm totally impressed. I'd recommend this mod to anyone.

Well I have a Recirculating euroreef 250 that I'm going to do tha mod once Tony sends me the stuff. I have 2 pumps on mine :biggrin: .

here is a picture of my skimmer that i will mod again :mrgreen:


http://i38.photobucket.com/albums/e1...C/finalpic.jpg

What the heck ya doing to that skimmer now. :lol:

this is looking like a pretty catchy mod... heres a little twist to it. I have a CSS 65 and the ASM obviously has a much superior needle wheel. I'm just wondering if it may be possible to improve on this model by using the same mod?

I'm so convinced of this mod, I think *any* needlewheel based skimmer would benefit from the mod.

I even think that this could breathe new life into older venturi model skimmers with a few extra mods. For example, those skimmers usually had the venturi between the pump and the skimmer (and just had a regular old impeller in the pump). Change it around so that the venturi is on the pump intake instead of the output, mod the impeller, and see what happens. In fact I regret unloading all my old venturi skimmers now because I really want to see what kind of difference it could make.

In fact, I'm now so convinced of this mod, that I'm considering unloading my two beckett skimmers. And I *love* my PM Bullet-1 skimmer, it has been an absolute workhorse for the last 5 years for me, it's been an incredible skimmer so to say I'm ready to consider selling it and going to all meshwheels should say how much I believe in this mod now. :) I feel silly for waiting so long to try it.