Swimbladder is fairly complex problem because there are many different causes.
First - check all water parameters - chronic High NitrATEs can produce swim bladder problems.
Make sure you don't have lots of gunk in the gravel - H2S posioning may also cause floating problems.
After you make sure the water is perfect, try the following:
I see he's already try the peas. In advanced cases of constipation, this might not be enough. Try stopping feeding for a day or 2, then give a pea with a single grain of EPSOM's salt ... this may purge the fish out ... <I am assuming that this is an adult fish>. Alternatively, you can add epsoms salt to the tank water.
To prevent food related gut problems, feed sinking food & varied diet with greens, peas, etc.
You may consider using antibiotics, as bacterial infection of the gut may also cause floating problems.
Increase the water temp - to high 70's. This increases the fish's metabolism & help in correcting any problems. Note that fancy goldies are not tolerant of cold - esp. sharp temp drops & this is reputed to bring on swimbladder problems.
Salt is NOT recommended for swimbladder problems ... The extra salt in the water makes it more difficult for fish to sink, stressing it even more.
I have only treated one case of swimbladder in my goldies, & he responded to inceased temp & peas, so I never had to try the other treatment methods.
80 gal FW with 30 gal DIY wet/dry/sump.
9 fancy golds, 1 hillstream loaches, 1 rubber-lip pleco (C. thomasi), 3 SAEs, small school of white cloud minnows, planted.