Wait a minute

did you sneak that in, that you went to get fish today?... more fish? You're having fun now aren't you.
Yes, the most important part of the filter maintenance is simply gently rinsing debris out of all the media using the just-removed tank water in your catch-bucket from the substrate clean siphon session you are in the middle of (filter maint. usually takes place while the tank level is low, ie in the middle of the water change.) Sponges are submerged and gently squeezed and moved around. Trays of loose media are dunked and swished. All media can be left submerged in your now dirty bucket of tank water while you do other things to the filter box (meaning you might need a bit more swishing if debris settles back on the media before you return it to the box.) Next the media box itself can be cleaned with your hand under a tub faucet (for example.) (But obviously, not media under a tap.)
Now comes the hard part. You will need to be prepared prior to doing this the first time by having some small brushes. The best have bristles all the way around a wire core. The most important thing is to be extremely gentle and carefully observe how everything comes apart and goes back together. If your fitler manufacturer gives any instrucs, pay attention to them. Use a sponge (all tank sponges must never have been used with soap) to clean any film from the parts of the pump head that are inside the filter. Next disassemble the impeller, being extremely careful not to break the ceramic shaft the impeller spins on if it has one. Clean film from the magnet assemply and very gently use your tiny brush to clean the entire impeller. Next use the brush to clean the impeller well in the pump head. Clean the impeller shaft and return it to it's holder deep in the well (if yours works like that) and then reassemble the magnet and impeller and locking mechanism. There will be magnetic resistence when removing and putting back in the magnet/impeller assembly, that's normal but don't break your shaft. Use larger brushes to clean out any water pathways from the hoses to the impeller area if you see they are present and you can get to them.
Re-coat all silicone parts with silicone grease (yet another thing you'll need to find if you don't have it, along with brushes) On my eheim, there are basically 5 parts like this - the main seal between the filter box and the pump head, 2 gaskets between filter trays and 2 o-rings where the quickrealease for the hoses meets the pump head. I take off each of the smaller gaskets, coat my fingers with silicone and rub them all over with it and then replace them to their positions. I just leave the main box gasket in place and smear the grease all the way round it at the top of the filter box, doesn't matter if there's some excess here and there. SF, it may take you some weeks to gather the stuff and figure this out and that's no big deal, just do your media rinsings without the impeller maintenance the first time or two if need be.
Last thing before you're ready to move the box back to the fish room is to put the media back in the trays (oh, forgot to say you can replace your polyfloss every now and then if you think it needs it but often it can last a number of months with just squeezings before it gets less effective) and then don't allow anything to sidetrack you because of course the media will be out in the air in the box not submerged.. but it's not hard to place it back under the tank, connect the hoses and open the hose releases so that siphon action refills the cannister. It's ideal to allow the cannister to receive water a long (seemingly long) time before trying to prime and power the pump, that way the most air will get out first. Then when you do prime and get it running, you can lift (I'm assuming external cannister obviously, sheesh I've forgotten your filter type even with all these months

) the filter box slightly and tilt it very slightly at different angles off upright and vibrate it so that some air bubbles will go up, hit your impeller, make noise and then shoot out through your spraybar. If there's too much air it will stop your impellor and you'll need to quickly re-prime to not burn out your motor, having fun yet? It's all easier than writing it. In time it will be second nature.
Wow, you're lucky to have a PFK recommended store, I like that magazine. You're gonna be a good fishkeeper SF, you and Tom and that little hand puppet (forget his name.) Will enjoy seeing some of your fish eventually.
~~waterdrop~~
