That was pretty good, conversion gel can be risky to place in a test chamber because you never really know how the player is going to use it but it works well in here and I don't think there's any useful way it could be exploited. The only item I didn't need was the light bridge, I can see what it's there for but it's easier to just walk or portal past the turrets and knock them over. You might want to think about adding cleansing gel in here too, in case the player gets bounce gel on the sphere or the cube and either gets stuck somewhere the player can't reach.

I've got a little collection of chambers going and I'm always interested in feedback on each chamber or the collection as a whole. I'd be grateful if you'd have a look:
Elementary