I have a hydrometer I know it has to be rinsed out after every use.Also every so often to remove salt deposits to soak it in vinegar for 30mins then rinse.My question is how do I get the inside of it to dry as its an odd shape as surely the water used for cleaning could well cause problems if the hydrometer doesn't dry out properly.The Hydrometer I have is the aquarium systems instant ocean hydrometer.

As long as you are using freshwater to rinse it, just letting it air dry would be fine. If you want to minimize mineral deposits, just use bottled water. I have done that before with the Instant Ocean hydrometers.

Last year I invested in a refractometer!! You can get some inexpensive ones on Ebay. Last week my friend paid about $30 for a really nice one. Might be something to consider in the future. I much prefer them to hydrometers.

Thanks for info.Just with it being a weird shape I wondered about getting it dry.I'll think about getting a refractometer ,mind I have lost track of ammount of money I have spent on all my fishy stuff in past month.Surprised I'm not bankrupt