UPDATE… in case anyone is pursuing the Hyper-Compressed Ocean.
(If pursuing it, this post may save you time, if you have a bad memory, as I do. If not interested in it, don’t read the rest of this…)
What I realized (per Wowhead), when I was one fish away (Displaced Scrapfin) from the Ocean, is that THAT fish only spawns in the “alternate/future Mechagon island”, requiring Chromie to spawn with the quest “The Other Place”.
Problem is, the guy I was working toward doing the Ocean on, had NOT ever been to “The Other Side”, so he would have to wait for Chromie to spawn on Mechagon to get over there. Wowhead was implying Chromie only popped up perhaps monthly for this (I’d forgotten all of this of course).
After two days of having him sitting there and no Chromie, what I did instead was hop on my guy who HAD done lots of Mechagon, and who I remembered HAD been to “The Other Side”, etc. He’d done maybe 90% of the stuff in there, with the exception of the big wheeled mount.
I then re-did the Achievement “Secret Fish of Mechagon” on THAT guy, getting him the Secret Fish Goggles, popping him over to “The Other Side”, and got a Displaced Scrapfin within like 10 minutes.
Anyhoo… if you want the Hyper-Compressed Ocean, which requires completion of the Achievements “Secret Fish of Mechagon” and then “Secret Fish and Where to Find Them”, I suggest doing this on whatever guy you have who has ALREADY been to “The Other Side” in Mechagon, and who made the “Personal Time Displacer” item at Pascal-King. (if you played Mechagon island, in that expansion, you will know what this means)
If you never did that expansion, or Mechagon island, or went to “The Other Side” and made the “Personal Time Displacer” item, then make SURE to be in Mechagon every day and check for Chromie, as Displaced Scrapfin will be the time-gating factor for you. (we all hate those time-gating factors, right?)