Royal Pleco Died - why?

[soulFish]

Ok had a Royal Pleco for about 2yrs, grew him up from a little guy. He seemed fine even tough. He made 3 tank transitions, and fought off 2 boughts of ick.

Then two days ago he started hanging on the glass up close to the top. No signs of stress, no bloating or any physical signs of sickness. Then I came in last night and he's floating dead?

Any ideas? All the other fish seem normal.

 

[soulFish]

Nobody?

tested, 0 ammonia for far

 

[Dmaan.]

any signs of taking a good blow?

 

[Flash]

Nitrite? What foods? How's the other fish in the tank?

 

[soulFish]

havent tested for nitrites, food has been New Life Spectrum & Algae Waffers.

All the other fish look fine, no heavy breathing on anyone in the tank.