Review on Get Cleaner & Healthier Water with GRECH CBG-800 5W UV Sterilizer Hang-On Back Filter for 20-50 gallon/211 GPH – Black by Jennifer Holt

Pros: > UV sterilizer is very effective at killing algae > Protein skimmer was effective and useful - for months Cons: > Throw away the charcoal that came with the kit - very poor quality leading to dust/charcoal becomes dirt > Poor basket design - sponge and 2 media storage boxes are used: the boxes must be aligned exactly so that the media basket goes back into the filter and care must be taken to move it past the exit of the UV sterilizer. -- Not too uncomfortable, just a very tight fit and suboptimal water flow through the media due to small media box slots > There are two regulators/valves for flow rate and protein skimmer speed - the protein skimmer "valve" starts up after about 6 months Sucking air in use probably due to wear of the o-ring, in any case poor cheap design that bothers the user after a few months of use. > DO NOT place a sponge on the filter inlet as this will draw too much water through the protein skimmer and/or the pump will not have enough power to suction -- Again, no big deal, just a little frustrating > The clear plastic UV sight bladder on the Top of filter has come off, now water is bubbling through. I love the features this product has to offer, unfortunately the poor design made me throw it in the bin after 12 months of use. Constantly tinkering to make it stop sucking air isn't worth it. Purchase a canister filter and built-in UV sterilizer.