Hi. Here's my concept for your contest. Simple lettermarks are personalized for your business. this one is very unique to yours. Plus, it make clever use of negative space.
#3 and #5, could you expand on them by adding something that makes them shine, like a sparkle. The reason being, something that sparkle can represent it being clean. Just an idea, I'll let you be creative, but I really like the concepts thus far.
I'm so sorry about swapping the letters around. Here's a correction for that and I've added a few gloss effects to the text. I'll work on some other highlights as well.