I have a ripmax cavalier balance lipo charger and a storm 3s 5000mah 25c lipo

the charger lets me select balance charge for 3s lipo but i have no idea what amperage it should be doing this at and for how long.

i set the charge timer to 30 minutes at 2 amps and i was very disappointed with the result. only around 4 mins of time on the water.