Marineland - Magnum Canister Filters
Magnum filters are, IMO, a hybrid filter. They cannot be directly compared with the "true" cannisters (Fluval, Eheim, etc.), as their media chamber is much smaller. This can be easily compensated for by getting the Pro series, which includes the biowheel as the main biological filtration. On their own, Magnums are terrific mechanical filters, and quite decent chemical filters. They have high flowthrough, and come equipped with micron cartridges which are capable of water polishing similar to diatom filters at a fraction of the cost. Since installing the Magnum 250 on my tank, I've not been able to get nearly as much crud up from the gravel when vacuuming... most of it is instead trapped in the cannister filter. The Magnum 250 HOT is very easy to disconnect, disassemble, change/clean the media, and reassemble. The entire procedure takes less than 5 minutes. A great mechanical filter, and if the biowheel option is chosen, a very good biological filter as well.
I have two Hot Pros now and I love them. Very easy to clean, and since I started using them I have had a zero mortality rate. Crystal clear water, and very little change in levels (pH, ammonia, nitrite) between water changes.
The Micron Cartridge is very nice and works very well, but plugs quickly. The optional media basket is very small, really only useful for carbon and the like...no biolgical happening at all. As a backup to do an occasional water polishing (with the micron cartridge) fine, but as a main filter almost useless. Personally, I don't like having to have more than one filter per tank, so would never buy another Magnum.
The HOT Magnum's greatest benefit is its gravel cleaning ability with the optional gravel vacuum hose. It is so much easier to clean gravel with one of these than trying to watch what your doing in the tank and keep one eye on the bucket. Mine is exclusively used to vacuum gravel. I can take my time and get the entire tank cleaned up.
I, too, use the HOT Magnum for gravel cleaning and water polishing. In fact, I just got my second one for back up and added convenience. It is so much better to clean tanks in a more relaxed and leisurely manner and replace the same water back into the tank in a clean state, then do an accurate 15 to 25% water change. After the gravel clean/water change, I leave the filter hooked up for several hours to clean out the detritus in the water left from cleaning. The result is a sparkling clean tank and happy fishies. It's a very easy filter to use and well worth the money. Without the HOT Magnums, I probably would have folded up two of my four aquariums.
I have the Magnum 350 Deluxe - it is like the 350 Pro, minus the gravel washer and the biowheel (I also use an Emperor 280 and it has its own biowheel). It is easy to set up and very quiet. If you mount it below the tank (like I did) you may need to purchase some more hose. I found clear vinyl hose at my local hardware store. Don't forget hose clamps. Shop around for price, especially on the internet. I saved $30 over my local petshops.