Yes! 60 fps on my old system
 

I got the Aquarium running at a smooth and fluid 60 fps on my old Pentium III 933 / Voodoo5 system.

800x600x16 (actually looks best in this resolution as the seaweed doesn't have that problem you get without AF) 3 fish and turned off bubbles and debris.

Still looks fantastic :-) I was surprised at how many more FPS turning off bubbles and debris gave me (especially debris, wouldn't have thought it'd use up so much CPU/GPU).

Of course my new system does everything on full at 1280x960x32 2xQ AA at 72 fps (72 Hz screen) but it's nice to get it running so nice on my old system too.

Yes! Turning off debris and bubbles gives a significant boost!

I rewrote the bubbles for the Mac version so that they are almost free.

Debris was resistant to such optimizations and remain very expensive. Fortunately, turning off debris doesn't detract much from the total experience.

Any chance of sharing your optimisation technique with the x86 coders?

I'm always happy to share.