RichConley
New member
Mavgi, how far into the fitting are you pushing the airline? Is it flush, halfway, what?
<a href=showthread.php?s=&postid=10326233#post10326233 target=_blank>Originally posted</a> by RichConley
Mavgi, how far into the fitting are you pushing the airline? Is it flush, halfway, what?
<a href=showthread.php?s=&postid=10327999#post10327999 target=_blank>Originally posted</a> by hahnmeister
Okay... now I have it. Its back on the skimmer body, and with the valve, Im over 40 scfh. It seems the pump has broken in a bit and it starts fine on its own as well.
Here's why I defended my venturi... sure, its longer, but as you can see here, there is no real difference, other that I can run this external, and not have to drill the impeller cover for the air intake. Its a copy of ATI's earlier design really...
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The air might have to travel a bit farther, but thats no big deal since there is no restriction, and its getting introduced at the same point as the ATI version.
The only debate in my mind is that a venturi isnt just about diameter, but length. My venturi is a bit larger (pink arrows), but its also contoured (so its even larger and then slopes down to 5/8" ID, or 16mm). But even though its larger in diameter, the length might have been what was killing it, as pressure drop due to diameter is also a function of length (a 1/2" nozzle will not drop pressure as much as say, a 3' length of 1/2" pipe... this is why you can run 1" pipe into a 1/2" nozzle at the end and still get great output, but if the pipe were 1/2" as well, you would see a pressure drop). My length, shown with green arrows, is many times longer than the ATI's. But I did bore it out so the intake was more than 5/8" even... about 3/4" actually at the intake.
Otherwise, the air and water combine in exactly the same manner and place... not that this is really important. I can now hit the same numbers even without the venturi just by adjusting the ball valve on the intake.
As it turns out, it was the zip-ties. The pump is much quieter as well now. Thanks guys. Im getting just over 40 scfh at 25 watts.
<a href=showthread.php?s=&postid=10340895#post10340895 target=_blank>Originally posted</a> by dudedudedude
Hahn, I have tried the Quite one 3000. Looks like I can get 30 scfh at 25 watts intank, and 40 scfh at 35 watts with 24" head on a primative 6 inch skimmer. Either way I have start up issues. I picked up on pentiar being sicce and have been working and moding it for about 3 months. I dont know if the 3000 will get the performance of the PSK-2500. However, the 4000 spins faster due to the windings according to pentair. I think this pump may have potential for equal to higher air flow at less watts than the psk-2500. If anyone has one I could borrow to test out for a week (it would not require any modifications) I could verify this.
<a href=showthread.php?s=&postid=10347457#post10347457 target=_blank>Originally posted</a> by LA-Lawman
mavgi, did i see the pump cover correctly. did you drill out the stock ATI airline connection. and if you did what performance gain did you see
<a href=showthread.php?s=&postid=10348019#post10348019 target=_blank>Originally posted</a> by mavgi
the true is that i don't recommend to try to increase more air to the BM250 because afer you will have problem with the size of the skimmer and you will need to increase the neck ,also you will need to match exhaust and so on , the skimmer work very well as is and i don't think it's necessary at all.
from all the test i did i can said that ppl should except from the Sicce 20-25LPM run into the skimmer