Raw rainbow fish

Raw Rainbow Fish is a members-only item on the OSRS Grand Exchange in the weapons category.

In-game examine text: "A colourful fish, attracted to colourful flies."

It has a Grand Exchange buy limit of 13,000 every four hours, a high alchemy value of 72 gp, and item ID 10138.

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Raw Rainbow Fish shows an active flip setup with a margin of +25 gp and 138,888 trades over the last 24 hours.

At the buy limit of 13,000 every four hours, max profit per cycle is about 325.0k gp — high margin with healthy liquidity.