How big is your air hole on your Durso ?

mirski57

Premium Member
This is getting very tough for me to figure out.
I started with the 1/16th...then I tried the 5/64th...then 3/32nd...then 7/64th...then 1/8th. This can't be right.....Durso's site says that 1/16th should be all you need. I doubt I'm pushing more then 1000-1200 GPH through this thing.
My Durso is 1 1/4 pipe with a 1" bulkhead; and my return line in my sump is NOT even submerged. Did the same thing when it was submerged too, however.

Anyway...I'm trying to get an idea how large everyone made their air holes in their Durso Standpipes.

Thanks,
Mirski57
(Bill W)
 
if your hole is to big, use electric tape or duct tape to make the hole smaller....

i'd love to tell you the size of mine, but with all the tape I cant make out a decent guess :p
 
I'm using a 1/8" hole in mine and I have about the same flow and size piping. It gets clogged with salt periodically and I have to clear it out but other than that works fine.
 
i had to use 1/32 hole all the others were to big for my system!
i have two durso's only put the hole in one of them work best for me.:eek1: :eek1:
 
Now my dusro has 2 small 1/8" holes in it, and for some reason, it just keeps starting a syphon, and surging back into the tank, it's all good though, cuz it's kinda like a surge device, LoL



DvS
 
with 1" bulkheads and 1" pipe i had to use a #10 (about 3/16) bit to get what i needed with 1100 gph.

i started out with a small bit like you and drilled a #40 and worked my way up and when i got to #10 it worked perfectly.

kc
 
No more cleaning no more fiddling with a mini ball valve like this. Just set it once and forget. You can adjust to any height in the overflow you want very easily and it holds indefinitely.

fb27d469.jpg
 
I have a 1-1/4" standpipe with a 1/16" hole. It will occasionally surge/siphon. This happens after I've stopped the main pump or had my hands in the tank. The surging usually stops in a few hours.
 
I use two small plastic air valves on my cap. Basically like Bowfront's set up. Not only does this rid the problem of finding the exact diameter hole, but sometimes it becomes necessary to adjust the valves slightly. This is almost always after I shut down the pump for a few minutes and especially after cleaning the pump periodically. I believe that after a shut down and start up of the pump and after a cleaning the pump becomes more efficient. I have a 55 with a single overflow and am pumping 1200gph which is maxing out the overflow. An additional 30 or 40 gph can raise the level in the tank just a little to close for comfort so I restrict air flow slightly and this lowers the water level. A day latter I just readjust and it is fine untill the next clening.
 
I used a 1/8th bit to drill the hole in my Durso for the 1 inch drain but I am also using a 3/4 inch drain as well in the same overflow with no durso (the 3/4" drain mouth is under the water level of the overflow at all times) so my setup is probably not the same.
 
Has anyone seen the NEW 'Durso' that All-Glass stole and is now manufacturing? My new 65g came with one... just picked it up yesterday.
 
Back
Top