how to release resource of one time particle system

hi all,
 
i'm a developer from shanghai,

i use babylonjs' particle system to show a water spout, each time a bomb hits the water.

each time i will new a BABYLON.ParticleSystem,

then start it.

and i set 

particleSystem.disposeOnStop = true;

after several times, the frame rate slows down, start to block.

i log scene.particleSystems.length

out,

the number keep rising.

the particle system seems not disposing itsself.

is there a solution to avoid the issue?

i use it the wrong way?

if can't solve it,

i may have to write a particle system and manage it myself.

any suggestions?

thank you.