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7.1.4 MALE ADAPTERS - FEMALE ADAPTERS:

A fitting with an outside thread that can be screwed into a fitting with an inside thread is called a male adapter. The one with the inside thread is the female adapter.

Common male adapters have one side threaded and the other side will usually be slip, so pipe can be glued into that end. The female fitting has thread on the inside on one end, and a slip end on the other, again to glue in pipe.

These fittings are needed to hook up pumps, and can be screwed over the threads of the fittings that the pump housing itself is outfitted with. Always use Teflon or PTFE tape when using fittings with threads. Alternatively, use a liquid, pasty, material that serves the same function: preventing leaks from threaded fittings. Tighten down by hand, or use a wrench if necessary. Never over tighten. You may crack the fitting.

7.1.5 BUSHING-REDUCERS:

A fitting that is used to reduce the size of another fitting to the size that you need. For example, to connect a 1 inch piece of pipe to a ¾ inch piece, you will need a coupling that has been bushed down with such a fitting on one side to ¾ inch.

Such fittings are also needed when you need to split up a water return line from, for example, one ¾ inch line to two ½ inch lines. In such a case you would use one ¾ inch Tee and two ½ inch bushings.

Instead of using separate fittings, in this case bushings, to do the job, you can also buy fittings that have the sizes you need. Such fittings are then referred to as reducing couplings, or are given their fitting name with the dimensions of each opening. For instance, a Tee fitting to do the job above, can be referred to as a Tee ½ by ½ by ¾.

This may sound somewhat confusing, I know. There are so many different fittings available that even plumbers get confused sometimes.

7.1.6 BARB OR HOSE ADAPTER:

A fitting that is made to take plastic pipe on one side and flexible hose on the other. Barbs come in male threaded, slip, and female threaded versions. Specify which one you need when ordering. The side that takes the flexible hose is ridged to give the hose a better grip once it is on. If you have problems fitting the hose over the barbed end, submerse the end of the hose in boiling, or very hot, water for a minute or so. This will soften the plastic and make it easy for you to make the connection.

Whenever you soft pipe (use flexible hose) your tank, you will need several barbs to do the job. For example, on the input and output side of your pump you will have the use the required barbs before you can hook flexible hose up to the pump.

Whenever you use barbs, you should also use worm clamps to tighten the hose in place so it can not slip off, or leak due to the pressure in the line. Use 316 SS worm clamps. They will resist salt water for much longer. Alternatively use the newer plastic clamps that you can tighten with a wrench.

7.1.7 NIPPLE:

A fitting that has outside thread on both sides. You may not have any need for this fitting around the tank, other than making a male adapter out of a female one, by screwing the nipple into the female fitting, after you have used a little Teflon tape around it.

You could also use it to connect pipes that both end with female fittings.

7.1.8 UNION:

A fitting used to make a connection between two pieces of pipe, but in such a manner that the connection can be undone.

For example, if you had a union in the pipe on either side of a pump, you can take the pump out of the arrangement by unscrewing the unions. Of course, if you have water in the sump, which is highly likely, you would use a ball valve/union combination. Such a ball valve is called a true union ball valve.

Unions are frequently used in long runs of pipe to make removable connections. In aquarium setups you may wish to consider doing so too, for example if you think you may need to take the piping down at some point (e.g. if you were moving). All pieces can then be easily reassembled later when needed.

7.2.1 BALL VALVE OR SHUT-OFF VALVE:

Ball valves and shut-off valves are used to control the flow of water through your system, or to isolate parts of the system so you can remove portions of it, e.g. the pump, or a canister filter that houses a micron cartridge.

In the former case you would use just a plain ball valve, in the latter case you would want to use a true union type ball valve, as the union part will allow you to disassemble the portion you want to take apart, without water spillage.

It pays to buy a good ball valve. Pressure from the tank on the valve will cause it to leak if it is not. Moreover, if you use ozone in the system, some valves will not last for very long. Recommended brands include Hayward, Asahi, Chemtrol and G+F. Keep in mind too that ball valves need to be cleaned from time to time. Not doing so may damage the valve, or cause the valve to leak when you try to shut it off because detritus is trapped inside the shutting mechanism.

7.2.2 CHECK VALVE:

Check valves are meant to do just that: check. This means that they will prevent water from flowing in the opposite direction of the one that you wish it to flow. They are one-way valves. Check valves are necessary in any water line around your tank that could back siphon if your pump failed or if you had a power failure.

Ball checks and Y-checks are the better ones to get. Check valves with a piece of rubber or similar compound, in the form of a flap will not hold up for very long around the reef aquarium. Salt in the water, and maybe even ozone, will ruin such valves in no time.

Keep in mind that the difference between a good and a bad check valve is very important to you. It could save you from a flood and an empty tank with, probably, many dead animals if you do not notice what happened for a number of hours.

They are a safety feature. You must install check valves in all systems that work on water returns through the bottom of the tank. You must also clean check valves regularly. Hopefully you will never need them to protect the system, but if you do and if they do not work properly, you will have a big water problem on your hand, and more than likely you will have lost most of what is in your tank as well.

Check valves are best installed vertically so the back pressure of the water forces them closed if the need arises. Although dirty check valves may check partially, small amounts of water that can get through will empty your tank in a matter of hours, if you fail to notice what is going on. Why do they get dirty? Slime, parts of algae, and so on, can get caught around the seat of the ball and prevent the ball from correctly seating itself in the space provided for it, thus preventing water from flowing in the other directions (towards your sump rather than towards the aquarium).

Of course, as long as your pump runs check valves serve no real purpose. But installing a check valve is the same as taking out insurance. You hope you never need it, and you may be upset about its cost, but when you do need it, you will be glad you have it.

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