Review on 🔲 Dennerle Corner Filter (5925) in Sleek Black - Efficient Aquatic Filtration by Sony Bailey

I bought this Dennerle bacterial inoculation filter for a new aquarium. I've had three 10 gallon tanks in the past three years. Each aquarium has 1 puffer fish and some blue shrimp, that's all. I also have three other 5 gallon snail tanks to feed my puffer fish. In fact, he just polishes the water. Dennerle expects you to destroy a colony of beneficial bacteria every time you clean the filter. Dennerle also expects you to rely on aquarium bacteria, which is simply not enough for real fish breeders. There's a good reason why not everyone uses the Walstad Method. If you decide to use your own filter material in this Denerle filter, you will find that the maximum weekday output current is practically zero. The three-part design of the carrier body is also not very successful. It feels like cheap brittle plastic. The way the case closes around the carrier worries me that if you try to remove it for cleaning it will likely fall apart in your tank, dumping tons of detritus back into your tank. I have been using the Penplax Cascade 300 in one of my aquariums for almost 3 years and can say that it is by far the best in every respect. I can run the Cascade 300 with my own filter media setup non-stop for 2 months without losing much flow. Keep in mind that all of my tanks are heavily planted and scarce. I'm throwing this Dennerle filter in my "emergency" drawer and buying a second Cascade 300 after writing this review.