I just had a crisis occur in my 90 gallon planted tank and I need to make
sure it doesn't happen again.

The net result is I've lost a couple fish and put the others under a lot of
stress. My primary filter a magnum 350 died while I was away.
Unfortunately my significant other didn't realize what had happened. As a
result the plants were the only thing keeping the tank going.

I'd like to add another filter to give me a bit of a back up. I'm thinking
another cannister of some variety. Since I inject CO2 I don't want much
surface agitation. I've got about 18" vertically to work with in the
cabinet. What do folks recommend. I'd prefer it to be easy to clean like
the Magnum 350 although I don't like the outflow set up for the 350.

Thanks

Chris