About a year ago I purchased an SuperFish Aqua-Flow 50 from my local pet shop.
I paid £10 for it and I'm very happy with the product. I have used it everyday since I purchased it (usually turning it off at night) and so far have had no problems at all!
Good Points:
2 years warranty !! 2!!
I find the filter very easy to clean, it is easier to take apart and reassemble than most of the other filters I have used.
It is fairly quiet. I wouldn't say its silent but the noise it makes is easy to live with.
The spray output is a nice touch, rather than squirting all of the water out of one valve it spreads it out into a sprinkler like system which looks nice and creates air bubbles for the fish.Bad points:
The filter has to be placed at a specific water level. An exact amount of the filter has to remain above water level to ensure it functions properly. I have seen several filters that can be completely submerged.
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The tank I keep my goldfish in is about 30 liters and this product claims to filter up to an including 50 liters. It says on the box to replace the filter cartridge every month which I have been doing at a cost of a few pounds per time. I would defiantly recommend this filter to any fish lovers!
I give this product 4/5 stars!