Marineland - Magnum Canister Filters
I have two H.O.T Magnums, one pro and one basic unit. I have not been able to prevent air leaks in either one although the pro system loses its water slower; over a few days. I have replaced every spare part except the impeller and used both Magnum silicone and Vaseline on all gaskets. It is pain in the you know what. I have a Magnum 350 Pro which is a wonderful filter and gives me no trouble. I like Marineland products a lot, except for the H.O.T.'s.
I have been using a Magnum 350 on my 380 liter tank for about 2 years. It is a very good water polishing filter and is so much easier to use than a diatom filter. I run it continuously with the micron filter cartridge to get rid of any parasites. I found that I have to change the micron cartridge every four or five days to maintain a strong enough flow or else my bio wheel attachment does not function. I found in the past that the media container with the floss and bio wheels was not adequate enough to filter my tank as I had a lot of casualties. I have added a Fluval 404 filter to the tank and the difference is like night and day! I would recommend the 350 as an adjunctive filter in a larger tank, but never as the main filtration system. The Magnum 350 is very handy to clean the gravel it does an excellent job with the gravel attachment. The Magnum 350 canister itself is made of brittle plastic as well as the valves and are fragile and easily cracked. I have had some problems with the canister lid seal leaking which could have been a serious flood! On investigation it is not the gasket that has worn but the metal clips that snap hold the lid on that need to be bent back in shape to maintain a tight enough fit.
I purchased a Marineland Magnum 350. It is a real pain to even open the thing up as the O-ring falls off. The water polishing filters do not work. The carbon canister is poorly designed and easily falls apart. I think I will go back to the TetraTec hang on filter I had before, as this canister is not an upgrade.
In comparing the Marineland Magnum 350 Deluxe system side-by-side with the Vortex XL canister filter system I found the Magnum to be better designed on several counts - especially easier to set up and easier to maintain. I felt the Vortex had a few serious design flaws, such as having to tighten several small brass retaining screws against a thin bare glass canister and having a very heavy motor resting on top of that fragile glass canister. The hose that came with the Vortex XL was soft and collapsed easily, restricting flow, whereas the Marineland Magnum 350 system came with ample lengths of high quality crimp-resistant hose. Marineland's break-resistant translucent plastic canister and quick-release disconnects are the best alternative to the Vortex that I found. After months of maintenance and use I am very pleased with my Magnum 350 Deluxe system. As for the Vortex XL - I returned it for a refund.
Magnum canister is by far the best canister filter ever. We have a HOT magnum and a emperor 400 on the 55 gallon that has an oscar and it is crystal clear. We have the micron flter on for a week and then have carbon cartridge on the rest of the month. We have a magnum 350 with bio-wheel pro 60, fluval 403, emperor 400 on the 125 gallon and it is crystal clear all the time with the two oscars and 2 parrot cichlids.
I've used a Magnum HOT filter for about 5 years or so. One thing is clear, this is not a filter that will handle your tank by itself, it doesn't have adequate biological capacity. Most of the time I had mine on a 55 gallon tank, and had an undergravel set up on the tank as well. This works out well. I currently have it hanging on a 125 gallon tank, which I'm using a wet/dry trickle filter on as the main source of filtration. I'm retiring mine very soon, at least from full time service. One nice thing about the HOT's is that you can hang them on just about any tank for water polishing. I have to agree with other reviews that this filter tends to want to suck air if you don't get the lid aligned properly with the canister. Parts wise, the only thing I ever replaced on mine are the two gaskets inside, and the filtering sleeve.