Well I'm sticking with it for now - it's new, so I don't want to run right out and replace it just yet. Next time I think I'll read this forum before buying things .
I use the aquarium vaccum to prime. Just dunk the whole tube & head in the water, put the narrow end into the filter intake (with downtube off) and lift the big end out of the water. That'll dump about a half gallon into the filter. If you filled the filter with water before connecting it, it should be ready to go then.
From what I've seen - the best method is to listen and feel the resistance on the primer handle. The more resistance there is the more water it's dumping into the filter.
Tredd,
I've been using a Magnum 350 for about 10 years. I used one on a 125 with two Hot magnums with biowheels and I currently use a Magnum 350 on my 75g planted tank. They are very easy to prime and give you many options for media should you choose to add any. I usually only run the micron cartridge and it keeps the water crystal clear. If you look into this, make sure you get the magnum with the double disconnect valves for easier maintenance. Hope this helps.
Tredd,
Forgot to mention, the double disconnect valves also allow you to regulate the output. I keep my output low enought so it just barely moves the plants.
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