• Plumbing Primer - how to do it correctly

    Here's the return pump. This is a Coralife pump with a two year warranty. It moves about 800gph at 80w power consumption. While the documentation states it is 3/4" in / out, the threads are for 1" fittings.


    First apply teflon tape. Pump is on the right, tape in your left hand pulling it down toward you, then around at least six times to get a good layer. Tear off and smooth it out.


    Next apply teflon paste, making sure to apply it all the way around the threaded section.


    Very important point: When screwing on the other half of the union, make sure the retaining collar is in place first. This is an easy goofy mistake to make, which is even worse when gluing fittings together.


    Hand-tighten it as snugly as possible, and don't use a wrench. Cracking the pump's shroud is a terrible idea, so be reasonable.


    Whenever I install a union (as well as remove and reinstall a current union in use), I apply a thin coat of Silicone Grease. This is what the package looks like at Lowes.




    Apply it to the threads, then hand-tighten the giant retaining collar. Next time it has to be undone to service the pump, it will come apart instead of being frozen in place.


    Double check that the black O-ring is in place, then tighten the two halves together.


    Following the same procedure as above, do the same for the output side of the pump. Teflon tape first, going with the threads.


    Teflon paste




    Cut a small length of PVC pipe to connect from the union to the double-union-ball-valve (DUBV), and take a look at the layout. Again, pay attention to where the handle is to make sure it has clearance. Note: This is the second Mix & Match union I made as described on page 1 of this article. The threaded side screws onto the pump, and the slip side is what the plumbing is glued into.


    Rather than gluing right over the pump and risk dripping solvent on the body of the pump or inside the plumbing, remove the section that is about to be assembled and work on it over the drop cloth.


    Apply the cleaner primer first.


    Apply the cement and hold.


    Slide the retaining collar over the union section, then glue on the opposite end into the DUBV. Don't let the glue get into the retaining collar since it needs to be free spinning. Don't let the glue get into the ball valve either - matter of fact, be sure the ball valves are always open to allow ventilation so the glue inside can cure, and work the valve open and closed a few times to make sure it still moves fully as designed.

    Apply some silicone grease to the union's threads.


    And now that section is done. You'll note that this assembly is more compact that the first dry fit picture above. The glue allows the PVC pipe to fit more deeply in the two opposing sockets.


    The water needs to pump up to the top of the poly tank, but I want a Tee somewhere in that vertical riser to get a water sample for testing purposes as well as to do water changes into the sump. By doing a dry fit, I could see what might or might not work. In this first picture, notice the metal support bar under the walkboard on the right and you'll see how the horizontal run would be a problem.


    After that simple visual inspection, I cut off an inch of PVC pipe to bring the Tee fitting down enough to clear it.


    Time to glue that section together. Remove the portion that is about to be assembled to avoid dripping glue on anything important.


    Primer, cement, press fitting on one end and hold, then repeat with the opposite end. Don't forget to slide the retaining collar in place!



    Continue to uniseal installation.
    Comments 22 Comments
    1. drimo's Avatar
      drimo -
      You had to *slip* your lubricant of choice in there. That container would make a lot of vodka.

      Excellent series of articles! I am getting ready to plumb my new 40 breeder and this will help a lot. I already have most of the parts, just need a few more things for the plumbing. I'll write something up soon when I have time. Thanks for writing this!
    1. marks69's Avatar
      marks69 -
      i'm not going to ask how you found out the lube works well.lol
      for your ro di water you could also use the t first then 2 shut offs. that way if the ato craps out you can shut just that off and still be making water. my world seems to die on me so i try to make things easy to fix.lol
      nice looking work though.
    1. masharp1126's Avatar
      masharp1126 -
      Nice idea on using the plumber's silicon on the threads of the union, I hadn't thought of that.

      A couple of areas that I do use it on are; the round rubber gasket on all unions and tru-union or single-union ball valves, as well as I'll take my ball valves, close them all the way, and rub some inside on the ball section. Then open and close it several times to ensure it's lubricated well. Makes it easier to open and close them down the road.
    1. Tbeau's Avatar
      Tbeau -
      Where and how much for the container. I would love to get a 100 gallon one. I am in mid process of converting from 75 to 120 gallon tank. I use a 40 gallon now and is not to my liking.
    1. drimo's Avatar
      drimo -
      What is the difference between schedule 40 and schedule 80? Your double union ball-valve from Savko appears to be schedule 80; what makes that different than the schedule 40 double union ball-valve sold by Lowe's?
    1. mr. fix it's Avatar
      mr. fix it -
      great article marc. i've done alot of pvc work and would like to add a few tips. i was always taught to use sandpaper on the inside slip end of fittings, 120 grit works good it helps the primer to soften the fittings for glue up. i always use food grade silicone paste on o-rings, like on the unions, protien skimmers, or anything else with rubber parts, even suction cups. i bought a couple of 2 oz containers through amazon.com of if you have a scuba diving shop near by, there only 2-3 bucks each and last a long time. there's another pvc part i like to use when necessary, it's mainly used for plumbing repairs, it's called a slip fix. it comes in different pipe sizes, and is a telescoping repair coupling. it will adjust about 3", and has o rings to seal. lastly most of the time when working with threaded pvc fitting you only need to make them hand tight, don't crank on them with a wrench because you will split the female end. especially when working with bulkhead fittings.
    1. Hat39406's Avatar
      Hat39406 -
      Hey Marc, I may be seeing it wrong, not sure, but I would have the pump a few inches off the ground. For safety reasons. Just an idea. ;-)
    1. Sisterlimonpot's Avatar
      Sisterlimonpot -
      I knew when I read that those gaskets are used on skimmers that Astroglide would make another appearance, I shouldn't comment on the level, should I?.

      It makes me want to track down your other posts about the subject....

      Great article Marc, I need to add it to my favorites so I can link others to it. thanks.
    1. melev's Avatar
      melev -
      Quote Originally Posted by marks69 View Post
      for your ro di water you could also use the t first then 2 shut offs.
      Once the vat was full, that's exactly what I did. First I wanted to shut off the water going into the room, but then like you pointed out, I needed to isolate the line from the 265g and yet still be able to make water for the RO reservoir.

      Quote Originally Posted by masharp1126 View Post
      A couple of areas that I do use it on are; the round rubber gasket on all unions and tru-union or single-union ball valves, as well as I'll take my ball valves, close them all the way, and rub some inside on the ball section. Then open and close it several times to ensure it's lubricated well. Makes it easier to open and close them down the road.
      Good suggestions!

      Quote Originally Posted by Tbeau View Post
      Where and how much for the container. I would love to get a 100 gallon one. I am in mid process of converting from 75 to 120 gallon tank. I use a 40 gallon now and is not to my liking.
      I got the container from a seller advertising via Craigslist. Got it for $120 new, which was a bargain. He had 5 of them for sale at a vodka distillery, up in Richardson. It was just over an hour away, but I couldn't beat the price. Plus I got to bring home a bottle of vodka to try out.

      Quote Originally Posted by drimo View Post
      What is the difference between schedule 40 and schedule 80? Your double union ball-valve from Savko appears to be schedule 80; what makes that different than the schedule 40 double union ball-valve sold by Lowe's?
      The difference is the thickness of the material. However, I don't think the DUBV is Sch80 even though the fitting is gray. The connections looks like Sch40 to me - Savko.com sells these. A member in our club had three for sale once and I bought them since they were brand new. The SUBV (single union ball valve) at Lowes is a bad purchase, it turns out. I have a couple of those in my garage. If you take the union off, there's nothing to keep the ball valve sealed. The union holds the ball socket in place - once I took it apart in the store I had a bad feeling about it but it was in stock and I needed them. However, I never trusted them and put that project on hold. The Savko ones are excellent and easy to use. I highly recommend them.

      Quote Originally Posted by Hat39406 View Post
      Hey Marc, I may be seeing it wrong, not sure, but I would have the pump a few inches off the ground. For safety reasons. Just an idea. ;-)
      There's no need. If the poly tank ruptures, that thing will be flooded in an instant. But if there's a leak, the french drain is there to take away any water in the room. I doubt I'd find 1/2" of water on the floor; the body is high enough to keep the motor dry.

      Thanks for the extra tips, Mr. Fix It.

      Glad it helped, Sisterlimonpot.
    1. Snakebyt's Avatar
      Snakebyt -
      awesome write up as usual, great to see the tank coming together.

      I was unaware that there was a different glue to be used when working with spa flex, i have just used regular glue in the past and guess i was either lucky or the glue was made for spa flex as well. Next time i go to buy glue, i will defenatly make sure it is made for spa flex.

      thanks for the great write up.
    1. lurchix's Avatar
      lurchix -
      Marc:

      What purpose is served by having the union on top of the pump when there's a double union on the ball valve immediately above? 'Twould seem one of the unions there is redundant?

      Thanks, Lurch
    1. melev's Avatar
      melev -
      Habit more than anything. I prefer unions right on the pump's inlet/outlet. In this case, the DUBV was a slip fitting, while the pump was threaded. I suppose I could have got a coupling that was threaded on one side and slip on the other. That would have been about $.75 instead of the $2.50 I paid for my union.
    1. Muttley000's Avatar
      Muttley000 -
      Another great write up Marc! Looking forward to the tank plumbing article you mentioned
    1. Midnight's Avatar
      Midnight -
      I like to use silicone on all threaded fittings as opposed to tape and paste. Silicone seals great and makes turning of fittings super easy. Also when possible, when using unions I prefer to have the collar on the stationary side of plumbing instead of the pump side of the union.
    1. melev's Avatar
      melev -
      Quote Originally Posted by Midnight View Post
      I like to use silicone on all threaded fittings as opposed to tape and paste. Silicone seals great and makes turning of fittings super easy.
      How long do you wait for it to cure?
    1. Midnight's Avatar
      Midnight -
      Just an hour or so usually. I have done this on my pool plumbing and turned on pump immediately with 1 1/2 hp pump with no problems. The silicone really fills all the gaps well. Just coat the threads and screw them in, also works on bulkheads.
    1. DETANE's Avatar
      DETANE -
      Great write up. Definitely a large amount of useful information that will help many reef addicts.
    1. kitch40's Avatar
      kitch40 -
      Marc, my return pump setup for our new 125 tank rated 1250 gphall came with 3/4" od hose barbs,and the same size on the inlet tubes to the tank. is that big enough fittings or would it be good to increase the size? THX Marc
    1. melev's Avatar
      melev -
      I would increase the plumbing between the pump and the bulkhead. 1" would be good. This avoids pressure and restriction for the first 2.5' or so.
    1. kitch40's Avatar
      kitch40 -
      Thanks Marc