Double Durso Drain in Same Overflow Box

[FishboneAir]

Hello All - First post on the forum here and embarking on the setup of our first reef tank. First glitch out of the gate is that the 120G tank we purchased has an undersized drain and return line bulkheads in the overflow box to achieve ideal turnover rates. The return line is 1/2" and the drain is 1". The dimensions of the overflow are to small to go larger than 1" on the durso drain so I am contemplating drilling the return hole to 45mm to accommodate an additional 1" durso drain. I will then drill two 45mm bulkhead holes as returns in the top back of the tank on either side of the spill over box.

The knowledge and experience here is tremendous so I really appreciate any comments on whether or not this is a bad idea. The entire tank is non-tempered glass and I have experience drilling glass with a diamond hole saw. I am hoping to have the ability to achieve a 10x plus turnover rate.

Cheers!

 

[Young347]

Okay so I am not an expert by any means but at first with my 150 gallon I was under the impression I need 1500 gph turn over to my sump then I did some research and turns out I was wrong !!!!! Turn over to the sump and turn over in the tank are 2 different things. So to the sump you want 3-7 times turn over becaus rid the water turns over to fast your equipment in your sump does not have enough time to filter the water at all the 10-30 times is the flow rate of your power heads to turn over your display tank. Just to point out the tank was designed by a company with a 1 inch and. 1/2 inch hole for a reason it is all it needs as for all the people on the net with this 10 x turn over rate they do this just to say their systems can and do it is not what is needed. And the emerging drains are not needed also why because with a sump built right to your tank the water lol in your display tank will allow for the extra water in your return section of your sump!

 

[South City]

If you want to move the most amount of water down your drain with two 1" bulkheads to work with, your best bet is to go with a Herbie drain. The link below takes you to a website that does a great job explaining how it works. The full siphon that you get out of the Herbie will move significantly more water than a durso.

http://gmacreef.com/herbie-overflow-reef-tank-plumbing-method-basics/

Hello All - First post on the forum here and embarking on the setup of our first reef tank. First glitch out of the gate is that the 120G tank we purchased has an undersized drain and return line bulkheads in the overflow box to achieve ideal turnover rates. The return line is 1/2" and the drain is 1". The dimensions of the overflow are to small to go larger than 1" on the durso drain so I am contemplating drilling the return hole to 45mm to accommodate an additional 1" durso drain. I will then drill two 45mm bulkhead holes as returns in the top back of the tank on either side of the spill over box.

The knowledge and experience here is tremendous so I really appreciate any comments on whether or not this is a bad idea. The entire tank is non-tempered glass and I have experience drilling glass with a diamond hole saw. I am hoping to have the ability to achieve a 10x plus turnover rate.

Cheers!

 

[South City]

Plus, you don't even have to drill holes for the return lines unless you really want to for aesthetic reasons. You can just bring the return lines right up over the top of the tank.

It may just be me, but when it comes to drilling holes in very expensive pieces of glass, I don't do it any more than I need to.

 

[sleepydoc]

Ok, I can't understand the last half of Young's post, but I wouldn't necessarily trust the company's interpretation of what the design needs are. Flow requirements are very different for a Fresh water vs salt FOWLR vs LPS vs SPS tank, and as I'm sure you have already noted, there are many different ways of setting up an overflow.

First, DO NOT try to drill the tank! The bottom is most likely tempered and if you try to drill the hole(s) larger you will shatter the glass and destroy the tank.

The corner flow, reef ready tanks are not designed for how most people run their tanks. You have several options:

1. Run a low flow 'traditional' overflow with the rhttp://www.beananimal.com/projects/silent-and-fail-safe-aquarium-overflow-system.aspxeturn through the ½" bulkhead like you're thinking. This will be loud with a lot of splashing, salt creep and be prone to flooding if the single standpipe gets clogged.
2. Run a durso - this can be quiet, but your total flow will be limited to a few hundred gph before it starts gurgling. Again, this is prone to flooding as it has a single point of failure.
3. Run a Herbie overflow with your return line coming up over the top. This lets you upsize the return for better efficiency and flow and has the benefit of a backup, making it less prone to failure.
4. Take out the corner overflow and drill the back for a beananimal overflow. (Also see bean's web site) - this is generally considered the 'Cadillac' of overflows but is more work to put in.

The best/easiest option for you would likely be the Herbie, but it depends what your goals are. After starting with a herbie and running that for 3 years, I just got done taking out the overflow and replacing it with a coast to coast with a bean system and am very happy with it so far.

Also, ½" is a horribly undersized return for most purposes. Unless you are running very low flows, you get extremely high head loss from the friction of the small pipe and end up wasting a lot of energy with your return pump. Yes, you can get a bigger pump, but you're just wasting energy and heating up your tank to overcome the resistance of undersized plumbing.

 

[FishboneAir]

All - Thanks for the input but I still don't think i have a solution for my situation yet. I know for sure the return is undersized at 1/2" for 120 gallon tank. Unfortunately, I purchased the tank without doing enough research first. I have followed up with the mfg and they are telling me the aquarium is entirely non-tempered glass and that customers drill them all the time, including the bottom.

I did consider the Herbie drain but my overflow box is in center back of the tank which, requires some turns to get the first chamber of the sump. This means I don't think it will hold the siphon. This is why I am currently thinking the double durso drain in the center overflow is my best option. I may not be able to drain a full 1200 gph but at least it would in theory double what it was designed to have. I am just looking for someone out there that may have done this setup and if it was successful.

Thanks again for the help!