I don't know about your particular filter but it takes a month or so I believe before all your biological filters mature so it's a fairly slow process. It's the bacteria that eat all the rubbish in the water to clean it up. That's why you should never wash biological filters out with tap water because it'll kill them and set you back to square one, hence why they recommend using a bucket of pond water
.
It looks like it's getting cleaner from your photos though.
I've a pond with lots of fish in and upgraded to a proper filter a few months back. With my old filter the water was murky and horrid but now I can see right to the bottom of the pond.. and I've been lazy and not cleaned the filters for a few weeks either!
KC Fibreglass Combo 12000 multi-bay filter (very nice owner - he personally dropped it of after a delay, and it's cheaper than the
Kockney Koi alternative too). I then filled the first chamber with
Black Knight Pond Filter Brushes to remove solids, the second with
Jap Mating as a high-surface area biological filter and
Alphagrog (inside onion sacks so it's easy to remove) as a final high-surface area / polishing filter.
I also ran a cheap
Jebao uv filter for a few months to clear up any green algae which seemed to help. I've a Jebao pump and they seem to great quality for the price to be fair.