One thing I notice is visable noise. I notice that the C5050 an auto ISO feature. Not sure if you are using this, but what ISO setting R U using? The color seems off as well, and I'm wondering if the image is underexposed, and then adjusted. That can also increase noise.
Do you use the histogram to judge your exposure when you shoot? If not, do so.
Even higher end PnS digital camera's don't do great at higher ISO's vs. their DSLR cousins that are very usable up to ISO's over 1000.
There is NO WAY you need a shutter speed of 1/1000 to stop action or to prevent blur that can result in handholding this camera, even if fully zoomed. 1/200 should be enough to get the job done, and even that maybe overkill.
The price you may pay in using a high shutter speed is increased ISO which results in noise, decreased DOF, and underexposure which can result in noise when the brightness is increased in software.
To give you a baseline, professional sports photographers use shutter speeds of 1/1000 to stop motorcycles in action. Any fish moving that fast is going to be out of the range of you camera long before the slow AF can lock focus, and you'd be able to pull the trigger.
Filling the frame more with the subject will help provide better focus which should result in sharper images. When focusing on any living subject, the eyes should be the focus point. A slightly blurry image of an animal with sharp focus on the eyes is acceptable in most cases. A sharp image of the rear end of some creature with the eyes OOF, is going to look wrong, and not be a keeper.
Ron