cant edit my other message:
ok it think these are these could be the ones, the eggs sound very similar:
Eggs: Laid below the water surface on the vegetation, packed in a gelatinous clutch. The size of the eggs is about 2 to 3 mm when deposited.
The eggs are visible as small white spots inside the transparant gelatinous mass that surrounds them.
During the development of the little snails, the eggs swell considerable (up to 4 mm). They also become more transparant and the little snails become visible as little spots attached at the inside wall of each egg.
http://www.applesnail.net/ (Marisa cornuarietis)
I only found 1 bigish snail (about 1.5cm) he had dark brow shell. all the others were tiny (like 1 - 3mm)