Ok, tell me what I did wrong

Little Luey · 08-07-2006, 08:02 PM

I am finally connecting my DIY skimmer, and I have water comming out of the ventury hole, here is my skimmer. I check to see if I had put it upside down but it looks like I did not. On the picture, the hose is where the poop is supposed to come out, the water goes in where the ventury is and the other pipe is the return. What did I do wrong? Please help.

Little Luey · 08-07-2006, 08:03 PM

the second picture shows the ventury as installed, the water come in from the bottom. I have a mag7 pushing water.
One thing I notice on mine compared to Geoff's is that my outlet is higher than the scum discharge hose, and he also has a "T" with a pipe taller than the skimmer, could this be the problem? I had the scum pipe going to a 5gal water bottle that I had seal, Barcocrish sujested I didn't do that because it was causing preassure, I am thinking, the skimmer could not release pressure and the only hole to relive pressure was the ventury, makes sence?

this is Geoff's skimmer
http://themantledmonster.thereeftank...s/skimfin.html

Geoff · 08-08-2006, 09:19 AM

how tall is the skimmer?

the distance between the pump and the valve may be to long. try putting the venturi valve directly on the pump. that way you have maximum back pressure on the venturi valve.

G~

Little Luey · 08-08-2006, 09:43 AM

from the pump to the ventury is about 20 inches. skimmer body as like 40 inches tall.
What about that "T", what is its porpouse? do I have to have that? How does the water "know " it needs to go the other way?

Geoff · 08-08-2006, 10:29 AM

the Tee i had was just to act like an anti siphon device for the sump it was attached to. it really did nothing else. if the outlet for the skimmer is below the water level of the tank than i would also put a tee on it where it goes into the tank to keep any back siphoning from occuring.

it is odd that water wants come out of the venturi hole while it is running. it will definatley want to come out of the venturi hole when it is turned off. that is the lowest point open to the atmosphere. i ran a long length of vinyl hose from the air intake of the venturi valve up above the collection cup of the skimmer to prevent this from happening.

G~

Little Luey · 08-08-2006, 10:37 AM

Quote:

Originally Posted by Geoff

it is odd that water wants come out of the venturi hole while it is running. it will definatley want to come out of the venturi hole when it is turned off. that is the lowest point open to the atmosphere. i ran a long length of vinyl hose from the air intake of the venturi valve up above the collection cup of the skimmer to prevent this from happening.

G~

this is why I had tought my ventury was upside down but when I blow in to it on the direction the water was flowing I get air going in to it. I am trying to move the ventury closer to the pump now.

Geoff · 08-08-2006, 10:41 AM

when the pump is running, you get water out of the venturi valve air inlet port? than definately move the valve closer to the pump.

G~

Little Luey · 08-08-2006, 10:51 AM

Thanks Geoff, I'll keep you posted.

Little Luey · 08-09-2006, 09:08 AM

I shortened the distance from the pump to the ventury, it did not do it. I think I am going in the right direction because it is a lot less water coming out of the ventury. I suspect the pump is not pushing enough water, it takes forever to get any water out of the outlet and when it does is a very week stream, I will try to use a bigger pump.
Just for the hell of it I took the ventury and flip it to see what it would do and a very constant and strong stream of water came out, so now I know it was place correctly.

hng · 08-09-2006, 09:46 AM

Some thoughts on how the two skimmers are different - the pipe that feeds into the skimmer is much longer in your skimmer than in Geoff's design. It runs straight up from the venturi and then has a long horizonatal run (looks like 16 inches) into the skimmer body which I would think would create a lot of back pressure. Try shortening the pipe into the skimmer as much as possible and see if that doesn't fix the problem.

Geoff · 08-09-2006, 10:06 AM

ditto, it does seem like you are getting a lot of back pressure on the backside of the venturi. i still would have thought a mag 7 would be able to push that though. maybe try going up a size on the inlet pipe.

still is strange. what do you have going on inside the skimmer? what does the inlet tube do once it is inside the skimmer?

G~

Little Luey · 08-09-2006, 12:23 PM

I have something similar to your skimmer, a 3/4 90deg elbow and then a tube about 8" long going down. I figure that will help get the water down beter for more contact time.

Geoff · 08-09-2006, 01:59 PM

try putting the mag 7 along with the venturi valve in the sump alone. does it produce a lot of bubbles that way? just wondering if your Mag 7 is behaving properly.

G~

Little Luey · 08-09-2006, 02:06 PM

I will do that tonight. Thanks for the help.

Little Luey · 08-09-2006, 06:51 PM

here is the latest:

I tried the mag7 with the ventury by itself and it does the same thing, water comes out of the ventury hole. Now, this pump was originally a mag5 but I put a mag7 propeler on it, I was told that it is the same body with different size propeler. Is this really true? when it had the mag7 it has a hard time turning, it pupms but it makes a ton of noise compare to when it runs the mag5. So if I can use it as a mag7, I can use it as a mag5 or I also have a Quietone rated for 1000gph and another one for 1300gph. the 1000gph pump is my return pump, which I could use for the skimmer and use the 1300gph on my return, I think the overflow should be able to handle it since I have 1 1/2 pipe there.
The mag5 worked ok with the 3/4 ventury so I will try that first.