Swamp Cooler Water Level Question

Hey all, so I did my first brew yesterday (a slightly altered version of northern brewer's bavarian hefe) and the fermentation began a few hours later and started to get very active (i've got a blowoff tube immersed in star san).

I live in Florida, and I wanted to make sure I'm cooling correctly. I've currently got the carboy in a bucket of water with a wet shirt over it. Ambient temperature is probably about 75, and I'm putting 2 ice trays of ice in it 2-3 times a day. There is a fan blowing on the shirt to hopefully aid in cooling.

My question is regarding the water level in the bucket. Where should it be in relation to the beer level in the carboy. Right now the water fills the bucket up to a few inches below the beer level, but I was thinking if the whole point of a swamp cooler was evaporative cooling, and so if that's the case then the water level should probably be a bit lower. Is this a correct assumption?

1) For a swamp cooler made up of a carboy in a bucket, what level should the bucket water be up to in relation to the beer?

If the beer level is higher than the coolant (water in the bucket)...then it could be warmed up depending on ambient air temps.

I don't have experience with the swamp cooler effect in regards to cooling your carboy, but I would agree with your suspicion that you don't necessarily want the water level very high. If the ice bath in the bucket is cooler than ambient air temperatures, then keep it high. If the water in the bucket is just meant to evaporate, then you'll need a shirt or fabric on the carboy itself so that there is more surface area to evaporate and draw the heat energy away.