It seems that if there is a sql memory leak somewhere and you dont have time to find it you can use the load balance timeout option in a sql connection string to destory the connection after x seconds.
Am i right in assuming I can set the load balance time out to 30-40 seconds and then hunt for the leak latter, while in the mean time the leak will not affect my application too much.
No. The Load Balance Timeout is the minimum time for the connection to live in the pool, it will not limit the life time of connections.
You might be looking for the Connection Lifetime setting, which will force connections to be closed when they are too old when returned to the pool, but that won't help you either, as the problem is that the connections aren't returned to the pool in the first place.