Interpet PF Mini

I have just bought a couple of Interpet PF Mini filters for some small tanks to grow our fry. I have previously used Hagen Elite Mini internal filters for this as they retailed for under £10 each and were very low powered, but they appear to no longer be produced. The PF Mini has a recommended selling price of £15.99.



This is the bit that always gets me: most manufacturers do not list the dimensions of the filter, so I’m going to go ahead and fix this here. It’s 140 mm tall, 60 mm front to back and 43 mm wide. With the mounting bracket on, it is around 65 mm front to back and with the addition of the outlet nozzle, it comes to a hefty 100 mm front to back. The power cable is around 130 cm long.

Power and ratings

It’s a 5W heater, which costs £8.76 to run for a year, assuming that one pays 20p per kWh. Interpet claims that the flow rate is 200 lph, but do not specify if this is with or without filter media, and that it is suitable for tanks up to 35 cm long which are 5-40 litres in volume. It is rather good of them to market filters specifically for shrimp and growing on tanks, but it does make me wonder if this encourages some people to keep fish in tanks that are too small…

Filter media and capacity

The filter takes approximately 110 ml of media and comes with two rough “wool” sponges, a carbon sponge and a fine “wool” sponge. I plan to run this filter lined with fine filter wool and filled with porous ceramic media as I find those easier to clean and they are already cycled.


As with most filters, this one comes with an instructions booklet. This “most advanced and comprehensive filter available today” from “UK’s leading aquatic equipment specialist” comes without any references for those statements. To be honest, I don’t see how a basic internal filter can be considered “advanced” when we have self-cleaning, programmable filters available from Eheim.

Having said that, the explanation about the nitrogen cycle is pretty good and the advice about replacing filter pads is spot on at “never replace over 50% of the filter media at a time”. They even recommend liquid or tablet test kits to monitor water quality and specify that tap water will kill filter bacteria. The only improvement here could be to recommend 20-25% weekly water changes for the “average” (read, “overstocked and unplanted”) aquarium instead of 10% every 1-2 weeks.

Replacement parts

As the Interpet website does not currently have the booklets available online, here is a list of spare parts that are available for this filter:

  • Flow deflector: 2180
  • Impeller and housing: 2181
  • Mounting bracket: 2184
  • 3× suction cups (sucker set for bracket): 2183
  • Media housing (filter body): 2182
  • Rough wool foams: 2230
  • Carbon foams: 2231