I would still get a Mrfunnel its worth it weight in gold for what it does. Even if you don't have microbes going the water can still be a problem. All jet A fuel farms have some water in them. They are vented to the atmosphere and when it humid out the inside of the tank will get water on the dry spots like sweat. We have a 12000 gallon tank and its very normal down here in Florida with all the humidity to have water in the bucket on a daily sump. Best protection is the MR funnel going into your fueler.