Standpipe and Plumbing Qs

[rooroo]

I got my new tank this weekend. Same size, 65 gallon, just with a corner internal overflow. Its a perfecto, so it came with a huge standpipe and return with the modular piping. Very cool, but I'm not sure if the standpipe is what I should use. It kind of looks like the durso standpipe but it doesn't use a Tee fitting, just two elbows, and has two holes drilled in the side of one elbow, then a 1/4" hole at the top with a little piece of rigid airline tubing. Anyone have experience with these standpipes and how they do?

 

Also I'm considering trying flex PVC instead of rigid PVC. Only thing is I have an external pump, and I've heard you should use rigid for the return with external pumps. BS or true? And all rigid connections will work with flex PVC, right? Glue will too?

 

TIA!

[davelin315]

The key with the Durso standpipe is that you need to have a certain basic shape at the top to correctly do the drain. You also need to have the pipe size reduced at the bottom in order for it to work correctly. If you are not comfortable with it, replace it with your own stuff, but my guess is that whatever you've got will work. As long as the water does not fill above the pipe itself or cover the air hole at the top, you're fine.

 

As far as flex PVC, I have never heard that you shouldn't use it with pumps of any kind. If you look at the original purpose for this, it's actually called spa-flex, and so it's intended use is with an external pump for a jacuzzi or hot tub. So, my opinion is that it is perfectly safe to use. It does allow for a little bit of play in the hose so you can reduce head loss by curving instead of bending, so I personally feel that it has advantages over schedule 40 or 80 rigid PVC. That said, if you're trying to make it so that things don't move around and have the pipe support itself, you can use the rigid PVC instead. If you look around at what (IMO) the average DIYer does, it's typically a progression of sorts through different types of tubing. Most start with the silicone tubing as it's easiest to use, then realize that the silicone tubing bends and reduces head too much and move on to the braided silicone. This is where some opt for the spa-flex instead. I still use a combination of the braided silicone and spa-flex in different applications because they each fit different applications. Bottom line is that it won't hurt you to use the spa-flex and there's nothing wrong with running it on an external pump (I think it would be a ton more difficult to run it on an internal pump to be honest with you as you're dealing with running it out of a sump of some sort and might need more severe angles with it).

[kngfisher]

If you have a 1 inch bulkhead the standpipe needs to be larger than the bulkhead to work correctly. Typically if you use 1 inch PVC pipe on a 1 inch bulkhead you get poor results. (Some exceptions with smaller low flow tanks.) For very large tanks with large return pumps however, there does not seem to be any need to oversize the standpipe for larger bulkheads such as 1.5 inch. Larger bulkheads can use PVC pipe & fittings that match the size of the bulkhead. (I consider tanks in the 350 gallon and up good candidates for 1.5 inch bulkheads).

 

-----above taken from http://www.dursostandpipes.com/

 

I have 1.5" durso conected to 1.5" overflow connected to 1.5" drain....works like a champ.....have also seen dual durso setup in one overflow box but the tuning takes more time...

[Charlie97L]

the perfecto megaflows work great. they have larger piping on the 1" bulkheads. they were designed properly, and are perfectly matched to what the overflow can handle.

 

my 90 perfecto overflow/durse stuff works like a champ. quality design.

 

the only mod i had to make was stuff a piece of filter sponge under the siphon break hole... once i did that the tank is virtually silent.

[Rascal]

I use flexpvc on my return from an Iwaki 70 - about 15 - 20 feet of it. Also on my drain lines. No problems whatsoever. In addition to the noise and head loss reductions, I like the fact that there is some "give" in the plumbing so that if I accidentally bumb a pipe while I am working, I don't worry about cracking the tank. Maybe I shouldn't worry about this anyway, but I am a worrier. The only disadvantage I can see is cost. It works exactly the same as regular PVC - except it's flexible. You can use all the same fittings. I still use a couple of 45's here and there when it needs to make a sharper turn. Works fine with unions, ball valves, gate valves, . . .

HTH.

[rooroo]

Thanks everyone. I'll look into the flex pvc. I've only worried about rigid pvc when trying to close/open a particularly tough ball valve. But that stuff seems pretty strong.

[Guest beatle]

I have a new Perfecto 90g w/the corner overflow and the standpipe. I found that the stock standpipe flushed like crazy until I replaced the the U with a more traditional looking Durso. I soon scrapped my Durso as well for the "Herbie" method of draining due to noise.

 

I now have both bulkheads in the overflow acting as drains. I stuck a 1" pipe into each. One is shorter than the other - tuned to match the output of my pump with a valve. The water covers this pipe entirely. The second pipe is a backup drain in case the main drain becomes clogged. My return is now run over the back of the tank.