How to properly plumb a tank?

[globaldesigns]

Originally Posted by lastlight

I never bother leaving pipe gaps but this is good advice. I don't bother with unions but I do buy schedule 80 true union ball valves. they'll turn smoother much longer than the crappy white guys and you can disconnect the plumbing where the valve is.

When do you really need to disconnect everything? If you want to do so make sure you're able to turn the entire lower leg of plumbing otherwise the threaded connection won't be much good.

Please take Bretts advice... I had the cheapy ball valves, and just a couple months ago, I had to cut apart my plumbing as one ball valve actually broke at the handle. Kinda scary, cutting things apart, as plumbing was also cracking when I tried to cut. Got it all put back together with the good valves as Brett stated, with also unions, for easy access, replacements, etc.

I only replaced the return plumbing valves, but the drains are still the cheap ones. I don't ever turn them, but use to adjust them for flow... But you can see that the handles are bent, as they never turned easy, and as time went on they got worse. They now run full open, and I will only turn them if in an emergency, but I do see myself replacing these also one day.

Don't cheap out!

[globaldesigns]

Oh Yeah, Western Pump is the place to go... When I was there recently, their PVC selection was HUGE, they had it all, and the pricing is great!

[jostafew]

Good advise from previous posts. May I suggest placing the ball valve ABOVE the union so that you can seal off the tank above before disconnecting the plumbing below? Also it may be a good idea to change from rigid PVC to flex or preferably hose for the last leg to the return pump, that section of hose will limit the vibrations from the return pump transmitting through the rest of the system.

As mentioned I would leave atleast a couple inches of pipe between the bulkhead and the next fitting so that you have some meat to cut off and modify the plumbing below if necessary (changes, or if you need to pull the tank off the stand). After that keep things as compact as possible and just glue (PVC cement) everything together that's a slip fitting. In the event that you have to make changes to the plumbing a possible few bucks in fittings will be a small price to pay to have some extra working space in the cabinet. Threads are OK but they can creep salt if you don't thread tape the snot out of them and are pointless if there are any 90's in the line (probably won't be able to rotate the fittings to remove them). Slip fittings will be more compact and easier to assemble. Don't forget to measure twice and cut once!

[globaldesigns]

Originally Posted by jostafew

Also it may be a good idea to change from rigid PVC to flex or preferably hose for the last leg to the return pump, that section of hose will limit the vibrations from the return pump transmitting through the rest of the system.

+1, very sound advice... I have done this, and agree, it does lower the vibration to all the plumbing. Also a nice way to disconnect everything from the main plumbing to the return pump, just in case you change pumps, and have to alter the connections. I have changed return pumps 3 times, and this had made things very easy.

[jostafew]

One other coment I forgot; do yourself a favor and orient the union so that the side with the groove and the rubber o-ring are on the bottom facing up, that way it won't be prone to falling out of the top half when you're trying to assemble things.