Im replacing all my balls and guides this year on the course I maintain in a public lake. Can anyone offer some advice on filling the balls and buoys with water? Like, how am I going to get water into a bike pump?? I would like to reduce their exposed height. I have an EZ-Slalom course and in the past have used gladiator balls and the giant yellow foam bouys. I need fairly durable guide buoys/balls since it's public.