Read all the DIY Nurce threads but still need help...

[Big Worm]

I am setting up a 7g MiniBow on my desk at work. Have everything good to go except for the topoff system. I am going with the DIY Nurce because of its simplicity. I want to limit the number of electronic gadgets I use on this tank since our Facilities Dept. are quite strict.

The DIY nurce will be going in a cupboard that is mounted on the wall directly above where the tank will be. The space is limiting so I have decided to use either a 3 gal Carboy or a 3g hex tank w/ a piece of acrylic to seal the top. In either case, I will be sealing it completely w/ a 2-hole rubberstopper I have.

Here is where I need help. I have read that the diameter of the tubing used can make or break the setup. The rubberstopper limits the size tubing I can use to regular rigid airline tubing. But from that point, I can increase the tubing size. What is the smallest diameter tubing I can use and still have the thing work?

[ronl]

Big Worm,
I have 1/2" tubing on my DIY Nurce and have never had a problem. It should work even with 1/4" airline tubing as long as you modify the end that goes in the tank that controls the water level. When the water level in the tank drops, the end of this tube must suck in air for the siphon to work. I think 1/4" airline tubing may sometimes hold water in the end because of the small hole. If it holds the water and doesn't fill with air the siphon will not work. If you take a couple inch long piece of rigid tubing that fits snug over the outside of the 1/4" airline tubing so that the rigid tubing is in the water it should be more dependable. Also cutting the tubing at an angle increases the size of the hole to allow air in. I have never used 1/4" tubing on my Nurce and it may work without an adaptor on the end, but I have seen people use the adaptor in their designs.
HTH,
Ron

[Big Worm]

Thanks Ron....

I happened to be at OSH yesterday so I picked up several feet of 3/16 I.D. flex tubing. What I am going to do is, instead of using the small gravel vacuum like many others, I have fashioned something similar out of a piece of a 1/2" sprinkler riser w/ a screw-on drip irrigation cap. The 3/16" tubing slips snuggly onto the cap. This should work for the air uptake end of the nurse. I will probably use the 3/16 tubing for water line too. I will make a "bracket" out of acrylic to hold everything in place.

I will post pics in about a week.... should have it runnig by then. Hopefully it will work.

[reef93]

hey big worm,
if you don't mind little noise from air pump you can look at my DIY topoff:
http://hometown.aol.com/pliang93/DIY.html

[Big Worm]

This is a pic of the air intake end of my DIY nurce:

http://cubanreef.tripod.com/topoff2.JPG

It is a piece of 1/2" sprinkler riser w/ a drip irrigation fitting screwed to the top. 3/16" tubing is attached. I cut out a piece of acrylic and attached it to the tank lip w/ silicone as the "bracket". It has a hole drilled in it and the riser is slip in. I still have to cut the riser at the desired water line but I can do that until I fill the tank.

I also plan on drilling another small hole to fit a piece of rigid airline tubing for the water in inlet line.

SO... what do you think.... any problems that you can see w/ my setup thus far?