Compact, powerful and silent

EHEIM compact ON is the compact and yet powerful aquarium pump. Available in eight sizes, for flow rates from 170 to 12000 liters per hour.

The EHEIM compact ON aquarium pump is characterized by its name through a compact design and is thanks to the included accessory bag appropriate for versatile use – the EHEIM compact ON 2100-12000 can also be modified for the use outside of the water. Thanks to the high quality material it is also possible to use them without problems in marine water.

For even more flexibility, the flow rate is adjustable for all models, except for the EHEIM compact ON 5000/9000/12000. EHEIM compact ON 300 is already appropriate starting from 170 liters per hour, EHEIM compact ON 600 starting from 250 liters, EHEIM compact ON 1000 starting from 400 liters, EHEIM compact ON 2100 starting from 1400 liters and EHEIM compact ON 3000 starting from 1800 liters. EHEIM compact ON 5000/9000/12000 is designed for a flow rate of 5000/9000/12000 liters per hour.

Compared to the pumps of the EHEIM compact/compact+ series the power consumption was again improved by up to 50%. Also the delivery head is presentable and makes the pumps powerful enough also for the use in the filter basin.

In order to guarantee a silent operation of the pumps, various measures have been taken like for example choosing a combination of ceramic axis and ceramic cover at the wing part of the EHEIM compact ON 2100 and 3000. This also guarantees a long service life of the pumps.
A high security standard has been attached like to all other EHEIM products as well as for the aquarium enthusiast as for the aquarium inhabitants. The cables are characterized by a thicker insulation and to the benefit of the aquarium inhabitants only materials which do not dispense toxic substances into the water, have been used.

The use in and outside the aquarium is possible for all pumps of the EHEIM compact ON 2100 series.

Advantages of the EHEIM compact ON

• Successor of the compact and compact+ series
• Fastening by means of robust suction cups
• Including accessories such as suction basket and threaded coupling
• Silent due to ceramic bearing (EHEIM compact ON 2100/3000/5000/9000/12000)
• High pump performance at low power consumption
• compact ON 5000/9000/12000 as electronic version for more efficiency

Compatibility

12,000 litres an hour, fixed. Like the 9000, this is an electronic compactON without a flow controller; it runs at its rated output. Plan the plumbing around that rather than around throttling it back.

EHEIM publish 110 W at 50 Hz, a maximum delivery head of 4.2 m, water connections at ø25, ø32 and ø38 mm and a body of 110 × 175 × 185 mm (w × d × h). Cable 2 m.

It fits Indian mains without an adapter — the European build is 220–240 V at 50 Hz. Media temperature range is +4 to +35 °C.

Freshwater is confirmed; marine is not, quite. EHEIM’s description of the compactON says the material quality means the pumps can be used in salt water without problems, but the specification table for this individual model ticks freshwater and leaves the sea-water row empty. Those are both EHEIM’s, and they do not agree. We are not going to resolve it for them — if this pump is going into a marine system, ask us first and we will get it confirmed before you order.

Indoor use, maximum immersion 1 m, water not above 35 °C. EHEIM class the compactON as protection class II and rate the body IP68 for permanent submersion, but the appliance itself is approved for indoor aquarium use only. It must never run dry.

Setup & Use

Submerged or dry-mounted. EHEIM’s manual for the 5000/9000/12000/16000 carries a section headed ‘Installing the intake nozzle for external use’ and states plainly that the pump can be used inside and outside of the aquarium. Submerged, it sits below water level on the mounting plate with the suction cups fitted. Dry-mounted, it goes on a stable surface outside the tank and the suction cups double as vibration dampers.

A note on EHEIM’s own copy. The general compactON description still says the 2100–5000 can be converted for use outside the water. The model-specific manual for this pump says otherwise, and the manual is the document with the fitting instructions in it. We have gone with the manual.

Cut the connectors to your hose. Both the outlet connecting piece and the intake nozzle are stepped cones that you saw off at the step matching your hose. EHEIM recommend a hose clamp on each. Water connections on this size are ø25, ø32 and ø38 mm.

The filter basket clips to an adapter rather than straight onto the housing as it does on the 5000. Pull it off to clean it, rinse under running water, push it back.

It starts the moment it is plugged in — there is no switch and no flow control on this size. Position it first, then power it.

If it switches itself off, that is the electronics doing their job. This size has rotation control that detects a dry run or a blocked impeller and stops the pump; after ten restart attempts inside a minute it shuts down completely. Unplug it, fix the cause, plug it back in.

Use pliers on the impeller. EHEIM print a pinch-injury warning for this size specifically: the magnet pulls hard enough to trap fingers while the impeller is being removed or refitted. On reassembly, line up the marking on the impeller with the marking on the motor housing.

What’s in the Box

• The pump
• Mounting plate
• Suction cups (they screw into the mounting plate)
• Filter basket and its adapter
• Threaded connecting piece for the outlet, to be cut to your hose
• Intake nozzle for external use, also cut to your hose

EHEIM publish no formal packing list for the compactON. The above is taken from the accessories they name on the product page and from the parts their manual has you fit during commissioning. Check it as soon as the box is open and tell us inside the 7-day window if anything is missing.

Warranty & Support

This product carries a 3-year manufacturer warranty from the date of purchase, covering material and manufacturing defects. EHEIM excludes wear parts — impeller, sealing rings, hoses and filter media — along with glass damage, units that have been opened, and any unit fitted with non-EHEIM parts.

Warranty support is handled by us directly. Message our WhatsApp support with your order number and we will diagnose the fault first — most cases are solved by replacing a single part, so you rarely need to send the whole unit. If the item does need to come back, it ships to our Delhi or Pune warehouse, whichever one served your order, and courier cost in both directions is borne by the customer. Your GST invoice is valid proof of purchase for the claim.

Returns & Replacement

Returns are accepted within 7 days of delivery, provided the item is unused and in its original packaging. Manufacturer-sealed items cannot be returned once the seal is broken, and sale-priced items are not refundable.

If your item arrives defective or damaged, message us on WhatsApp with your order number — or email us, if you would rather — and we will replace it. Approved replacements are delivered within 3 to 5 business days. Transit damage is covered by insurance on every shipment. If tracking shows delivered but nothing reached you, tell us within 72 hours, which is the reporting window Indian couriers allow. Damage caused during installation or use is not covered; replacement spares for such cases are chargeable.

Full terms are on our Cancellation & Returns page.