Filter Problem After Partial Water Change (Fluval Edge 23l)

The fact that it is dribbling shows he pump is working. The usual cause of diminished water flow is blocked filter media, blocked by uneaten fish food, fish poo, bits of dead plant etc. Take the media out of the filter and have a look. If it is covered with goo, you'll need to wash it. I know you've just done a water change, but take a bit of water out of the tank and swoosh/squeeze the media in that - gently, you don't want to dislodge biofilm with all its bacteria.
While the media is out, you could try just turning the filter on for a few moments to see if the flow is OK. If it isn't, it could be debris in the impeller well. Check the filter manual for how to open the pump part to get at the impeller. Be very gentle as some filters have ceramic impeller shafts which are fragile. Use a cotton bud to clean the inside of the impeller well.

Hi Sunshine, just wanted to say "well done" i'm still newbie and things going wrong panic me, im on here asking questions before ive even tried to sort it out lol. Thank goodness for google too lol. What fish have you got? 

Your bacteria will be safe unless you grossly overdo the cleaning. Filter media has to be cleaned regularly, the usual advice is to clean one bit at a time, but I clean the whole lot at once with no problems. The bacteria live in the biofilm which is tightly bound to surfaces including the filter media and it does take quite a lot to remove it. Your filter media will never look like new again so don't scrub it too much in an attempt to get it back to new condition

Carbon isn't necessary on a routine basis but it is useful in some circumstances (it removes medication once treatment has finished, and it removes the brown colour that leaches out of wood)
The worst media for clogging are those made of filter wool. This can be as the outer layer of cartridges or a pillow stuffing-like layer. It also doesn't make that good a home for the bacteria - sponges and ceramic noodles are better - but it does remove fine particles from the water. Filter wool usually has to be changed quite frequently, but as it isn't there long enough to grow many bacteria it is safe to just throw it away.