yep, blow over it with a rattle can, the pre/post performance delta will be unnoticeable to the user. In real terms at Ku band (Commercial satellite tv) you may see a drop of 0.2db. Rain fade will affect the signal more than this
I had the dish set up in the garden, whilst messing about with that HD receiver I bought, to replace the old SD one. This morning's little task was to dig out a rattle can, and blow the dish over, and shorten it's hammer in, ground pole. I keep any part-used rattle cans - when I have finished spraying, I simply invert them, blowing all the paint out of the pipe/jet, before storing them.
Amongst my collection, I found a can marked 'Granada White', obviously a left-over from when I used to have a diamond white Granada, maybe 40 years ago. Sprayed that, then had a go at reducing the length of my homemade, hammer into the ground, mounting pole. The dish kit had been bought with a variety of clamps, stands, and sucker bases to mount the dish on, none particularly stable, so I made my own version. A short bit of steel tent pole, flattened at one end, to go in the ground, then a brass adaptor, plus screw clamp, to clamp onto the D shaped peg of the dish mount. The pole was unnecessarily long, so whilst the dish was drying, I shorted that, reassembled, and hammered it back into the ground in a new position.
Now dry, I reassembled the dish, plonked it on the pole, and fired the system up. To my amazement, with no adjustment at all, it came on with BBC2 loud and clear. There was no noticeable change, in signal level. Job, jobbed!