WOW i made a discovery!!

hehe not sure if anybody has done this before.. but anyways...


i have a hang on back overflow. its the one they carry at aquatic dreams.. not sure on the brand...


well.. i was having problems with it not flowing very well... my mag 9.5 was outflowing it and i had to half throttle it down. so i went and got another tube from ryan and did a double tube... well this helped out a little but not much.. gave me another 1/8th open on my return pump line ball valve is all.. 


well i was ALSO having problems with it because it was INSANELY loud.. we are talking crazy loud. so i tried to come up with ways to quiet it down.

first i tried a towel over the top.. didnt even help... then i tried stuffing a dry towel down into it... this helped alot but still WAY loud.. so then i try a d a m p towel.. this was so far the BEST thing. quieted it down a TON.

well then i got thinking... i had some SCULPY modeling clay in my closet.. what if i  put it over the top of hang on back part of the overflow and close it up so the sound cant come out of there...  well i started putting clay on there and sealing up the top of it and all of a sudden i noticed my tank getting alot lower... im like WTF where is my leak!!! checked everything and no leaks.. then i notice that my overflow box in the tank is low and getting sucked in crazy fast. so i start thinking... WOW... sealingoff the top of the overflow box is helping my flow..

so then i crap a piece of acrylic, put putty across the top rim of the overflowand seal totally around the syphon hose. i put the acrylic on and seal around the edges and HOLY COW!!! my overflow box is EMPTY!! i hurry and throttle on my retrun pump to 100% and its STILL out flowing my stinking tank... the overflow box will not fill up.. just a constant typhoon of water getting sucked out!!

so it was WAY too much suction with the two syphon tubes so i take one out and seal it up again... this time its a little better.. but still WAY too much syphon. you guys seroiusly have no idea, it was almost a violent suction coming out of the box... my sump was pumping CRAZY hard on the overflow side..


so then i came up with an idea.... what if i take my air line off my skimmer, and stick it in the top of the clay and seal around it and make myself and adjustable overflow    so i try it out and VOILA!! i can now adjust how much air it lets in the air tight seal on the overflow box.. i can adjust the syphon and throttle my pump to 100% with no problems at all anymore.. i can also adjust it so that my box is always full and i dont have to listen to the water spilling over its sides..


in the end i ended up with a overflow that is 10000000%   silent... and can outflow my mag 9.5. and i mean MAJORLY out flow if i adjust it to not let any air in.. i am guessing it could probably handle about 1400 GPH.. it was just crazy..


anyways..  just thought id share my findings


Edited by LostCauseZ06

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Edited by LostCauseZ06

i googled it and checked it out.. but it doesnt seem to be what im talking about.. maybe the same effect or reasoning for it working?? (dont have time to read in depth about it)



all his pipes do are make it silent... the way mine was set up it increased the flow by INCREDIBLE amounts... which would make it possible for somebody with a bigger tank to run a hang on overflow and not worry about their return pumps overfeeding the overflow..



either way, ahha even if it is old news it was new to me   i thought it was a pretty cool little discovery i made guess maybe it wasnt my discovery after all ahha

jfinch wrote: A durso is a way to create a variable rate syphon buy metering in a small amount of air to the syphon.  It's the same principle you describe.  Durso's allow for very large flow rates and are quiet.  And they are very easy to build and adjust.

gotchya


but the only thing is that those durso's do not work and can not adjust syphon in a hang on overflow.. becuase a hang on overflow is charecterized by the flow in teh tube, not in the plumbing below it..

if i was to use a durso in my hang on like they do on their site all it would do is get rid of the noise in the overflow by keeping the water level high and lessen ing the distance the water falls... the actual water being pulled into the overflow from the box would be totally contingent on how much syphon the tube has going from the box to the overflow. i dunno if its common knowledge or what but all i know is that i learned that when you remove all air from the discharge end of the tube that it creates a SUPER syphon that FAR outperforms one  that is not sealed.. the durso pipe works the same way but is not really applicable to a hang on overflow in the same way as an in tank overflow.


correct???  i could be way off so keep in mind im asking and brain storming.. not telling you "how it is" , cause im sure you have WAY more expertise in this area than i do

Dursos can be used in a hang on the back overflow box.

not telling you "how it is"

No problem.  I'm not trying to tell you "how it is" either.  I have no vested interest in dursos other then I'm a happy duros "customer" .