I've had my dark green Pulsar dome for nearly seven years and I've washed / polished it most years, but recently it's started to look very faded and dejected.
I've tried various polishes and waxes but after a few weeks it always goes back to worse than before.
Now I've found some colour restorer called Owatrol Polytrol that says it's good for bringing gel coat back to life.
This stuff has good reviews and the best price I could find was on Amazon (about £25 per litre delivered). One coat took about a quarter of a litre. I'm going to wait for this coat to dry, then give it another wipe over, so I reckon it'll be about half a litre for the whole job.
https://www.amazon.co.uk/gp/product/B00E3VACQE/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
Here are some before and after pics of my efforts today...it was really easy to apply and looks fantastic, but the true test will be to see how it looks in a couple of month time. Watch this space.
By the way -Polytrol is a yellowy brown colour, so isn't suitable for white fibreglass.
Hope someone finds this useful.
Steve