Here is the full list of all 25 Glowfish achievements.
Locate 10 Secret Areas.
Circle a large foe into a friend.
Get a 4-Star Rating in any level.
Eliminate 100 enemies in Orbit Mode.
Collect 500 coins.
Eliminate 100 enemies by circling them in Chain Mode.
Trap an enemy creature between the moving walls.
Take 50 friends to safety.
Defeat Dr. Urchin.
Get a 4-Star Rating in all 50 levels.
No loss of glow on a stage.
Collect 5000 coins.
Upgrade your Glow Chums to maximum capacity.
Get a 4-Star Rating in 10 different levels.
Locate 50 Secret Areas.
Unlock all Glow Chums.
Convert the Corrupted Fighter into a Glow Chum.
Locate 25 Secret Areas.
Finish level 4 without harming any foes.
Win the Darter race with a 4-Star Rating.
Avoid the Angler Fish in the Briny Depths.
Take 500 friends to safety.
Upgrade Scout to maximum.
A perfect win over Dr. Urchin; no loss of glow.
Get a 4-Star Rating on any of the puzzle levels.