Aqua-internal filter 400 review


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Nathan Hill checks out this new Maidenhead Aquatics exclusive.

The first thing I see when removing this from the box is the reassuring IPX8 protection rating festooned across the side. For a fully-submerged filter, this is always a good start.

What hits me is the amount of silicone grease inside my sample Aqua-internal 400. The impeller seems drizzled and the seal ring between the impeller cover and the motor head seems to be spewing the stuff out. That’s no bad thing, but it might be worth rinsing before committing it to the tank to get shot of any excess.

The impeller itself is sturdier than a nuclear bunker. Chunky, robust and inspiring confidence, this moving part wins, hands down, against many flimsier-bladed rivals.

Annoyingly, the accompanying manual covers all sizes in the range and doesn’t dwell on the fittings that come with this large model — but it’s all pretty intuitive anyway.

Flow can be adjusted, with rates of 200-800lph emblazoned on the opposite side to the IP rating. However, it is only controllable with a chunky nozzle accessory that starts to make the whole thing look like the subject of a documentary about Soviet era plumbing.

On the plus side, this thing belts out flow. With or without the included spray bars, it’s as though the unit simpy screams water. Having spent time with many pumps that claim to have high flow rates, I know this one backs its claim with macho flair. Very impressive.


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