I'm not familiar with that model, but it reminds me of a very expensive Eheim canister filter I had many years ago, and though that was a great filter the first two years or so, the last year I had it , it started having problems. It sounded like the impeller was spinning , but no water movement, and it's only now I think perhaps there was a crack or bad seal somewhere that wouldn't let it prime properly. That's terrible for a very expensive filter, but I was moving about that time and gave it to a friend along with my other aquariums etc. and just hoped he could get it working again. Have you checked all the seals , gaskets, etc, if it's even a canister type. As mentioned I'm not famiiar with that filter!

How old is the unit? The impellers do need to be replaced from time to time, I keep one on hand because it usually happens to me when the stores are closed! Make sure everything is seated properly, even a tiny bit off and the filter will lose it's prime. Also make sure that the blue hickey in the back is pulled up and not on the 'feed' mode.

Petsmart carries parts for various filters. Also you only have a 42 gallon tank, I know you are a student, but why not buy another filter. I like the Hagen Aqua clears. They work with a sponge system, and I think they are much more realiable. Good prices for these are at pet solutions on the internet. www.petsolutions.com. Petsmart here in my town was selling aqua clears for 50% more than pet solutions. Walmart has nice filters for not to much money. You are lucky you only have 42 gallons, so equipment is not too expensive. To get yourself by till you figure this out. Go and buy a sponge filter and attach it to a cheap air pump. Soon you will lose all your good bateria. You need to get to petsmart fast. This is why I usually run more than one filter in my tank. I have been known to run a power filter and a box air driven filter, etc. Always have a backup. There are lots of very cheap backups. Using cheap air pumps as the driving force. The motto to have fish by (it is not if the equipment will fail, but when the equipment will fail).

If you plug it in dry, do you hear the impeller moving?

Also, fill the reservoir up with water to start it.

(This _is_ the type with a biowheel,right?)

my emp400 isn't working either but i think its cause i dont have the tank water all the way to the top.

i'm slowly filling up the tank.
but you would think it would be powerful enough to prime without the tank full.

i hear the impeller, i fill the filter full of water.

Take the motor off the filter body and plug it in, make sure the impeller is spinning well and put it back together while it is running dry, hang it in the tank and add water, after it primes and starts running put in the cartridge. Sometimes you have to do this to get them to start right. I agree the Hagen Aquaclears are more dependable I have a couple that are almost 20 years old, I have replaced a couple of impellers, but the still work. I also like the foam sponges, and the carbon bags they use. I only replace the foam blocks when they get too old and clogged to clean, and I buy empty filter bags and carbon and make my own carbon bags.

The manufacturer says dont run it dry!
This is a pain in the azz. My whisper60 runs alot better!
But I'm going to try what you say.
Put the empty cartride closest to the inside of the tank?
& the carbon bag furthest away?

It will only be running dry as along as it takes you to put it back together, hang it on the tank, and add water, less than a minute if you are familar with how the filter goes together. I think what they really mean is not to leave it running dry for long periods of time, because it will over heat. I've never had a problem doing this, to get one to start, work fast!!!!

To take off the motor its only "unsnap it"?

The intake tubes: do you want these really tight together or
when you assemble, only push them lightly together?

On the surface it looks like emp400 is more powerful & sturdier then the whisp 60...

but on both, if i squeeze too hard, it's going to break very easily.

Some other thoughts (per my experience)

Really look at impeller. I've found almost invisible threads, hairs, ie floss from other filter, imbedded (wrapped) around metal tube (small part where thing is at end).. have to take tweezers and pull it out, more and more comes out.. where did it come from how did it get there but stops thing in its track.

I often (as poster mention) have to take stuffing out(I don't use cartrige (too expeisive) and use my own charcoal so on... fill with water first then start then add stuff. no idea why but gets it going

Also, sometimes tilt it while hanging off back out a little to change input somehow (not sure why but works)I keep adding water from tank with cup to get it going.

(tilt meaning from bottom of filter away from tank) some larger ones have this plastic thing that keeps it out from tank other don't but that tilt makes difference when starting up.

reread instructions, I missed stuff early on and found solutions re cleaning all parts leaks so on.

On one the rubber part (if thinking of same) had gottin tilted so pushed it back into place - not sure how long it will last until breaking down.

Make sure on start up, tank water level is high enough(when going doesn't seem to matter as much) keep adding water until it gets going.

sometims after it just won't work with tank, I take it off (frustrating) and go into bathroom, fill a large metal bowl, fill with water and empty filter water only and see if it runs with motor. does, so go from there, (usually the impeller clogged with threds of something again they get embedded around and around) very hard to see but lots come out once you start pulling. if that's the cause)

I fill with water, and start up. Make sure top part tube pushed in far enough, tilt this way and that. Have to keep water level up high enough and water filled. then suddenly it starts. Then I move back to tank, hang, water in, and start add stuff, stops.. rince repeat...arrgghh!

Go to freecycle.org (type in your state) and sign up and ask for free (all things are free, giving and asking for) for what you need, may find. best Sherry

I enjoyed freecycle for awhile until it got to the point where people where posting wants for things like Money, Houses, and cars.

hmmm, didn't notice here in NYC. Funny I gave away a 75 gallon, then when I posted for help with rescue paccu kept in 10- gallon at pet store (egads!) same person whom I gave 75 applied saying she'd take it... had 600 gallon, so took three days to transfer fish from local pet store to me to her (gently).... all in all a Kharma sort of thing... You give you recieve, lol... I was greatful, no one else responded! The fish now is one happy camper... Best Sherry

I just got my pump working on Eclipse Six system. Soaked the impeller in vinegar to dissolve gunk, then rinsed. Also put some plastic around bottom of impeller housing to make a better seal. Thanks for your suggestions!