Saltwater Aquarium Plumbing Tips

by | Aug 15, 2004 | 0 comments

Choose slip and clamped barb fittings over threaded fittings for fixed plumbing whenever possible.

Use the specified adhesive(s) for the material you’re gluing (spa flex and rigid PVC use slightly different glues, for instance) and follow all of the recommended steps (prime, glue, slip with a twist, hold; etc.). If you can, attend a Home Depot workshop on home plumbing when you know they’ll be covering PVC.

Test all of your plumbing under normal operating conditions, preferably for several days, before subjecting any living thing to dealing with it. I like using food-safe dyes in fresh water to help find any leaks during these tests.

Try not to turn too many corners in a plumbing run, and if you must turn a corner, don’t use a 90 degree elbow unless you absolutely have to. Use spa- flex (flexible PVC hose), a sweep (a rigid PVC pipe with a large radius bend in it), or two 45 degree elbows… but avoid 90 degree elbows where possible.

When plumbing with spa-flex (flexible PVC hose), it will almost always have a “set” that follows the curve it got when it was wrapped around the roll during manufacturing. Don’t try to fight this “set”, instead try to use the bend it already has to your advantage.

Plan your plumbing ahead so that you don’t have to wedge it or bend it after gluing to keep it where you want it. Once attached, vertical runs should end up exactly where they’re needed without any additional support and longer horizontal runs should only require the occasional strap to keep them from bending under their weight.

Test-fit your plumbing before gluing anything.

If you make a mistake with slip fittings, it is possible to drill out the pipe in the fitting and try again, but it will almost certainly be simpler and less trouble to buy more fittings and pipe. Test-fitting your plumbing before gluing anything should prevent most of the “go back and buy more” type mistakes.

On any bulkhead that leads to or from external equipment (return pump, skimmer, etc.) make sure that there is a ball valve very close to the bulkhead and a union on the other side of the ball valve. A true-union ball valve is even better. You’ll eventually need to disconnect the pump or skimmer for repair/maintenance/replacement and this will let that happen with little mess and no fuss.

On the output line of return pumps, put a union and then a ball and/or gate valve close to the pump where you can get to them. A gate valve is better for throttling the return flow, the ball valve is faster to turn off and less hassle if you don’t need to throttle the flow. Again, this allows you to disconnect and repair/maintain/replace the pump without disrupting your aquarium.

If you have an in-stand sump, have a plan for how to get the sump out of the stand without tearing the tank and stand apart. Smart placement of unions is again the not-so-secret trick. The litmus test is to complete all of your gluing with the sump outside of the stand, fill the main tank, and then move the sump into place. Only after the sump is placed under the stand do you actually complete the various assemblies (these final steps should not use any glue). If you can get it in, it’s likely you can get it out later. Do not try to momentarily pull on or otherwise force things to get the sump in or out of the stand. You will probably weaken joints and cause leaks.

Do not put restrictions in drains. Even though it’s a good idea to have a ball valve to shut down a drain for tank maintenance, throttling a drain with a partially closed valve is a bad idea. Something will eventually catch in the restriction (snails are famous for this, with hair algae the next most likely culprit) and your drain will clog. Unless you have a second drain that can handle the full flow, your return pump will continue to pump the contents of the sump back up to the main tank and the main tank will overflow.

Use of a standpipe (Durso, Stockman, etc.) can be great for quieting overflow boxes and their drains. Don’t glue the parts of a standpipe together as you’ll want to make occasional adjustments.

Once water starts flowing through your plumbing it will be a little noisy. Once the pipes accumulate a little slime inside (a week to ten days of running salt water through them) this will quiet down a lot. Be patient and buy some earplugs in the meantime.

Quiet a noisy external pump with a neoprene mousepad or two (a good idea for any external pump actually).

— Ross (“rabagley”)

Wrap neoprene pipe insulation around the drain pipes to quiet the noise.

Remember to clean the inside edges of PVC pipe where you cut it – the little burrs etc… WILL catch debris that goes down the drain.

Use a gate valve instead of a ball valve – a ball valve will eventually clog with calcium and become impossible to close.

To clean items like an inline chiller or powerhead simply run it in water with vinegar.

Drill a couple of holes in the bottom of the flexible water pipe (where the water enters the tank from the sump) to prevent back siphon when the power goes out – even better is make sure this is just at the normal water level and it will break siphon automatically when the water level drops a little.

For long return plumbing a very slight drop is all that is required – say 1 inch per 10 feet – you are not trying to move solids like in normal waste plumbing just return the water as quietly and as gently as possible

To quiet the returm from a skimmer into a sump instead of letting it exhaust straight into the sump use a perforated pipe – it will not impede the water flow and will eliminate the splashing noise.

— “shellshocked”

If you put a bulkhead at 4″ below the top of the tank, and then put a Tee on the outside of the tank with a cap on top with a hole, and a hose on bottom running to your sump, you will almost have a durso standpipe. The only part you are missing is the elbow inside the tank pointing down.

— “knucklehead”

I like to use clear PVC glue and primer instead of the blue/purple color version. Works just as well and looks alot neater when done.

— “tgallo”

Plan your plumbing out 1ST. Make a list of every thing you need then add atleast one more of every item on that list.(for smaller parts like elbows add like 3 more). You can always retrun items that are not used. There is nothing more aggravating then having to run up to the store to buy a .25 plubming fitting. Once you have all the parts you will need “dry fit” them (no glue). Once your happy with how that looks, start glueing from the tank down.

— “TJG”

Valves & Unions:

  • Always buy threaded valves (not slip unless you never plan on modifying your setup) they are a couple of dollars more each, but they can be reused and reconfigured endlessly.

Tubing / pipe:

  • I prefer to use vinyl flexible tubing as much as possible. It is inexpensive, easy to work with and doesn’t require alot of elbows to get where you need to go.
  • If the tubing kinks when you’re trying to make a tight radius use several metal hose clamps to hold the tubing’s shape.
  • Placing the tubing in a bathtub with very hot water makes it more flexible and easier to work with.
  • When dry fitting rigid PVC pipe mark the connections with a Sharpie marker by making a line across the pipe and fitting. When glueing the joints, rotate the pipe so the marks align.

And last but not least:

  • You can get anywhere you need to go with three (3) 45 degree elbows.

— “jcurry@wesketch”

Always measure twice if not three times!

Buy a good pair of pipe cutters. These make a nice smooth cut and no mess from hacksaws. Also, great for cutting tubing.

If you end up using clear tubing in your plumbing, wrap with electrical or duct tape to prevent algae growth within your lines.

A nifty backflow preventative for those that plumb your return to bulkheads is to plumb your lines first above the waterline of the tank. Then plumb back down to the bulkheads. Insert a tee in the portion above the waterline and add a John-Guest or other speed fitting for 1/4″ tube. Run the tube to your overflow or anywhere else that it will spray into the tank and not outside. Now when your pumps stop your tank won’t drain to the level of the bulkheads because the tubing will draw in air and break the siphon and the water will stay the level of your returns or the level of your tank, which ever is lower.

— “Modo”

You can maximize the efficiency of your water pump by always full port valves and PVC fittings, increase the size of your intake pipe, and not use a prefilter that would restrict flow. Provide 24″ or more of piping from the pump’s outlet without any fittings or valves. Annually remove your pump’s impeller and give it a good cleaning. Look for signs your pump may be ready to fail, rattling, squeeling, and increased heating. When installing a new pump, never overtighten the fittings, you could damage the fitting, and the pump. Use teflon tape on the threads, and tighten hand tight, and then 1/4 with a wrench.

— “hillbilly”

Use vegetable oil as a lube to get tight-fitting flexible tubing onto barbed fittings.

— “Save_the_Expos”

These tips and more can be found in the Archives.