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hqgc
03-16-2007, 02:04 AM
I have a G2 and it will never produce more than a quarter of the collection cup of skimmate. I have tried different heights with the bubble level in the riser tube and still no different.
It currently sits in 8 inches of water. The water height can be increased, just not decreased ( the skimmer has no more room to go higher).
I don't know why I can't get more out of it considering in was a $400 touch.
The only question I have is should the lid on the collection cup be air tight? I know that it isn't but even if you wanted it to be I don't think the ASM's will go air tight.
Any help would be great.
Thanx
H.

midgetwaiter
03-16-2007, 09:31 AM
The lid shouldn't be air tight.

ASM skimmers are easy to setup so you might have some other things going on but here's a few questions to narrow it down.

What is the level of the output tube, have you raised it way up?

What level does the water come to in the neck of the skimmer?

How long has your tank been setup?

How long does it take to get that quarter cup?

Delphinus
03-16-2007, 04:13 PM
To be honest I have the same complaint about my G3x. (I think it's a G3x, if not it's a G3 anyhow). If I get a 1" of skimmate in a week that thing is doing well (I use the term "doing well" with a sarcastic tone).

One thing with mine is it's modified to be recirculating and is fed from the overflows, which I now gather is a "no longer recommended approach". Although I don't really think this is the problem with mine.

What I have noticed is that the venturi is *incredibly* prone to the slightest of blockages. What I've had to do is, on a weekly basis, take a nail (or other long thin tubular item, like a drill bit that you don't care if it gets SW on it), and scrape out that air inlet in the venturi. If I don't do this, the foam production will drop off very quickly after a few days. It seems that air inlet is really good at gathering a slime layer that impacts the airflow through it.

Some people drill out their venturi's to make the hole larger, and in fact some people remove the air inlet altogether and tap out the hole for a hose barb that allows more air in.

As soon as I get my airflow meter that I ordered, I'm going to modify this unit into a meshwheel (basically remove the needles off the needlewheel impeller and replace with two layers of enkamat). People are raving about this kind of modification on their needlewheel skimmers (any needlewheel) so it should be a positive move. I'm thinking I might also be trying the tapped hose barb mod on the venturi. I'll let you know how it works out.

hqgc
03-17-2007, 02:09 AM
The lid shouldn't be air tight.

ASM skimmers are easy to setup so you might have some other things going on but here's a few questions to narrow it down.

What is the level of the output tube, have you raised it way up?

What level does the water come to in the neck of the skimmer?

How long has your tank been setup?

How long does it take to get that quarter cup?

-The output tube is an inch above the bottom of the collection cup.
-the water comes about half way up the riser tube
-My tank has been up for about 5 months
-It takes about 3 to 4 days to get just under a quarter cup


thanx

midgetwaiter
03-18-2007, 07:33 AM
I thought about this for a while and still didn't come up with anything great to tell you. I'd expect more from it based on your bio load.

Has it always been about like this or has it produced better in the past? Is the stuff you are getting pretty dry? Check your venturi intake for any blockage like Delphinus described.

cprowler
03-18-2007, 04:32 PM
I have a G2 and have the same issues that you and Tony have. I have been doing the cleaning that Tony mentioned just not as often. I have considered doing the reserc and/or the gate modifications but am most interested in the mesh that Tony mentioned.

I didn't know if I just wasn't feeding enough (every 2 or 3 days :redface: ) or what.

Tony - Are you going to post your mods in a thread?

Delphinus
03-18-2007, 05:15 PM
Yeah, will do. I'm just waiting for the airflow meter to arrive in the mail so I can do some "before" and "after" measurements to be sure that I've made an actual difference. :)

FWIW, my G3 has the recirc mod and the gate valve mod.

hqgc
03-18-2007, 09:05 PM
Once my G2 hits max capic. after 3 or 4 days , that seems to be it. I am starting to wonder if it has to do with the "crud" that builds up at the top of the riser tube. Once it gets too "brown" and thick around the top that seems to be it, the skimmer stops producing. Its like that crud prevents anything from going over the top into the collection cup.
Does this sound familiar Tony and cprowler?
H.

mark
03-18-2007, 10:09 PM
I get the band of crud around the top as well, seems to have no effect, though when I empty the cup, I usually wash off.

Delphinus
03-18-2007, 10:13 PM
Hmm, interesting. I'll have to watch for that effect. It could be happening for me. But it's hard to say. Usually the skimmer works better after I've emptied and cleaned the cup, which could be explained by the crud preventing the foam from spilling over, but then I usually give the venturi a quick clean as well at the same time so it's hard to say, maybe the better initial performance is because of that instead.

Interestingly this last week I've gotten a half cup full of skimmate. It hasn't performed so well in months. Maybe it's heard me talking about the mods I'm going to make on it and it's trying to shape up :lol:

Honestly I do find that the venturi is very sensitive. Just a quick poke through with a nail is all I do at cleaning time, takes basically 10 seconds and it ensures there is no blockage starting. Give that a try maybe?

hqgc
03-18-2007, 10:23 PM
Hmm, interesting. I'll have to watch for that effect. It could be happening for me. But it's hard to say. Usually the skimmer works better after I've emptied and cleaned the cup, which could be explained by the crud preventing the foam from spilling over, but then I usually give the venturi a quick clean as well at the same time so it's hard to say, maybe the better initial performance is because of that instead.

Interestingly this last week I've gotten a half cup full of skimmate. It hasn't performed so well in months. Maybe it's heard me talking about the mods I'm going to make on it and it's trying to shape up :lol:

Honestly I do find that the venturi is very sensitive. Just a quick poke through with a nail is all I do at cleaning time, takes basically 10 seconds and it ensures there is no blockage starting. Give that a try maybe?

The venturi.... is that part where you hook the air tubing?
I think I will start threatening mine with some mods as well.

Delphinus
03-19-2007, 05:16 AM
Yep .. that's the part. I slip the tubing off, take a nail and push it into the hole, wiggle it back and forth a few times and replace the tube. It's a bit of a pain because it's really tight in my sump but it seems to be worth the effort.

mark
03-19-2007, 04:21 PM
Must have something to do with either the Ca levels are where kalk or reactor effluent is added.

Never had a blockage in the year+ my G3 has been up and the only maintenance I do on mine is to dump and rinse the cup and then every few months take the skimmer out of the sump and hose out the skimmer body and run some water through the airline.