Nice Cheap DIY Overflow

Everything I've read here says 1.25" works the best. Somewhere in the thread someone mentioned 1.5" and if I'm not mistaken said they were having some probs. You'd have to search for it. I don't have any issues with 1.25" and a Rio1700

 

I build mine with 1 in fittings and pipe I ran a 90 for yrs and yrs with a mag 9.5 then went to a Mag 14 and a simple one inch line to t he sump from the HOB overflow I did have to add a 2nd 1.in U pipe to feed the overflow but the drain handled the added flow just fine a 1 inch pipe will haul about 800 GPH on the average aquarium set up . with a couple of 90's and a few 45's on the way to the sump straighter is faster.

 

Thanks for the tips on size. Due to availability and after doing some calculations on the drain size at reefcentral I built another one with 1" PVC. I did a test run in a bucket and it seems to handle a fair amount of flow. We will see once I get it in the tank and pair it with the sump return pump. Any tips for improving flow rate other than bigger pipe?

 

Okay so I keep seeing this thread mentioned for the plans for building this DIY overflow "Double check these plans. http://www.sirensongboutique.com/ani...s/overflow.gif".

However this website does not work...Is there anybody that could send me a link or email of the plans?

Thanks in advance

 

I'm going to build one of these overflows tonight for my new refuge/sump, I'll post some pics when I get it done.

 

I am going to add yet another thought to this fantastic thread. The subject "tiny bubbles." I have a system using 1" pipe and a high quality check valve for priming. The system works great with a Mag 7 running at about half throttle. However, over time air bubbles form in the top "U" over the tank edge. I can pull these out through the check valve and all continues great. Over time I will lose the prime if I do not remove the bubbles. It was really bugging me as to where these were coming from. I have pressure and vacuum tested the entire system.

You might want to stand in front of your toilet when you think of this possible answer. In the Northern hemisphere our drain water spins counter clockwise, in Australia clockwise. I have been there and checked both. With the vertical suction pipe there is a substantial rate of flow. If you look at it you will find that it spins. As it spins fast (or if your pipe is too short) the center air vortex reachs the bottom "U" and some air makes through to the upward flow pipe. If you made yours from a clear PVC tube you can see this. So what to do?

I have placed a thin piece of plastic, much like a tape measure down the center of the inlet pipe. As it turns out my flow increased and thus far I am not creating bubbles. The vortex is substantially reduced to two smaller ones (either side of the plastic) and appear to not allow the air to reach the bottom. I will give a longer term update.

Anyone else tested this or thought about it?

 

I went through the exact same thing ,the vortex was creating bubbles in the top part, like you I stuck a piece of plastic on top so the vortex isn't as bad my flow also increased. The only thing I don't like is the amount of bubbles that come out in the sump/refuge, all I can figure is they are coming from the vent pipe.

 

I have to say that thus far the plastic ribbon has not worked well on my system. I still am getting air in the top. I think it is because I have a 90 degree inlet and the plastic ribbon probably makes the flow more agitated as it goes around this bend. But, I think there is a good solution so will continue trying different vortex spoilers. I think the air you are picking up is, as you say from the vent pipe. It may be from yet another vortex that goes to the sump. I have put a plastic film can cap over my 1" vent pipe and that not only reduced all of the sound but seemed to quiet down the agitation.

 

I dig this idea, I think I am going to try this out.

 

i joined this forum with the sole porpous of saying how great this thread is!!

i will be making this up next weekend! only problem ive got is that i cant see the design plan on the 1st plan, so i'm only going by the many pictures of peoples designs!

just so your aware my tank is 30" long, 18" high and 14" deep (around 130 litres I think), my sump is 20" long, 12" high and 10.5" deep

thanks Tony