JBL ProAir A50 Aquarium Air Pump Set

JBL ProAir A50 Aquarium Air Pump Set is a small diaphragm air pump supplied with the airline, stone and valve needed to run it.

Key Features

• Everything needed in one box: The pump, two metres of airline, an airstone and a check valve. That is unusual at this size, and it means the tank is aerated the day it arrives rather than after a second order for the bits.
• 50 litres of air an hour: JBL rate it for aquariums of 10 to 50 litres, which covers nano tanks, quarantine tanks and fry tanks without being wasted on them.
• Over 160 mbar of head pressure: Pressure is what pushes air down to a stone at depth. JBL's figure here is high for a pump this size, so it does not stall in a deeper small tank the way a cheap pump does.
• Built to be quiet: A noise suppression chamber inside and rubber feet underneath, which is where air pump noise actually comes from.
• Mounts outside and simply runs: A diaphragm pump sits outside the tank, plugs in and works. Nothing to prime and nothing to submerge.

How Air Actually Oxygenates A Tank

• The bubbles themselves add very little oxygen. Almost all gas exchange happens at the water surface, so what an air pump really does is break that surface and keep water circulating up from the bottom to be re-oxygenated.
• Which is why a stone positioned to disturb the surface does far more good than one buried under decor making a decorative column of bubbles.
• Oxygen is lowest just before dawn. Plants have respired all night without photosynthesising, so if fish are going to gasp, that is when they do it. Running air overnight and switching it off by day is often the right pattern.
• Warm water holds less oxygen than cool water. A tank running hot in summer needs more aeration rather than less, and that is the commonest reason a tank that managed without an air pump for years suddenly needs one.
• Fish hanging at the surface, gills working fast, or crowding around the filter outflow are the signs to act on. Add air first and work out the cause afterwards.
• Most medications reduce dissolved oxygen, and several say so on the pack. Aerate hard for the whole course of any treatment.
• On a CO2 injected planted tank, running air during the day drives off the gas you are paying for. Run the air at night instead, which is when the tank needs it most and when the CO2 should be off anyway.

Fitting It Safely

• Stand the pump above the water line wherever you can. If it sits below the tank and the power goes off, water siphons back down the airline.
• Fit the check valve regardless, close to the pump. It is the one part that stops a siphon starting, and on a pump mounted below the tank it is the difference between a damp cabinet and a wet floor.
• Leave a drip loop in the mains cable so water cannot track along it into the socket, and keep the plug above water level.
• Give it air to breathe. A diaphragm pump draws through a filter pad, so one shut inside a sealed cabinet runs hot and gets louder.
• An RCD on the aquarium's supply is a sensible precaution on any tank with mains equipment around it.

Keeping It Quiet

• Air pumps are the noisiest thing on most aquariums, and nearly all of that noise is vibration passed into whatever the pump is standing on.
• Do not stand it directly on a cabinet top or a glass shelf. A folded towel, a piece of foam or a mousemat underneath takes most of the hum out.
• Better still, hang it. A pump suspended from a hook touches nothing and so transmits nothing.
• Keep the airline slack. A line pulled tight carries vibration down to the tank and turns the glass into a soundboard.
• A pump that has become louder than it used to be usually needs a new diaphragm or a clean filter pad rather than replacing.

What Else It Will Run

• A sponge filter or an air driven box filter, which is the standard filtration for a quarantine, hospital or fry tank because it cannot draw a small fish into an impeller.
• A brine shrimp hatchery, which needs vigorous air to keep the cysts turning over.
• The drying line on an automatic feeder, which is what stops the granules swelling and jamming the drum.
• A protein skimmer or an air driven reactor on a marine system.
• More than one of those at once, through a splitter and air taps, as long as the pump has the output for it.

Looking After It

• Diaphragms are consumables. They harden and eventually split after a couple of years of continuous running, and the output falls away gradually rather than stopping, so it is easy to miss. Service kits exist, which means a tired pump is usually a repair rather than a replacement.
• Airstones clog with limescale and biofilm. As the pores block, back pressure rises, output drops and the pump works harder for less. Soak the stone in vinegar or simply replace it, since it is the cheapest part of the system and has the largest effect.
• Check the filter pad in the housing from time to time and keep it clean. A blocked pad starves the pump.
• Replace airline once it goes hard or yellow. Old line kinks permanently and splits where it meets the barbs.
• Run it continuously rather than switching it on and off through the day, unless you are deliberately running it at night only on a CO2 tank.

Choosing The Output

• The number is the air output in litres an hour. The ProSilent range runs A100, A200, A300 and A400, covering tanks of roughly 40 to 600 litres, and the smaller ProAir A50 covers 10 to 50 litres.
• Flow is only half the story. Head pressure is the other half, because the deeper an airstone sits the harder the pump has to push. A pump rated at the surface delivers noticeably less at 50 cm down, so a deep tank wants more pressure rather than simply more litres.
• Count what the pump has to drive, not just the tank. One airstone is easy. Two stones, a sponge filter and a brine shrimp hatchery on a splitter need far more than the tank volume alone suggests.
• Err upwards and fit an air tap. An oversized pump turned down runs quieter and lasts longer than a small one working flat out.
• Send us the tank volume, the depth and what you want to run from it, and we will tell you which output fits.

Good To Know

• The complete kit is the reason to choose this one at the small end. JBL list airline, an airstone and a check valve with it, whereas the ProSilent listing mentions a check valve but not the hose and stone, so ask us what is in the box if you are comparing the two.
• For 10 to 50 litres. Above that the ProSilent range picks up, starting at 100 litres of air an hour.
• A good size for a quarantine tank, a fry tank or a brine shrimp hatchery, where a larger pump would simply be blowing the water about.
• Indoor use. Keep it dry, off the floor and above the water line.