I built a fluid bed and I am using coffee filters as my media.  I did a test run last night and got it running and works well.  However after cleanup I noticed that quite a bit of powder paint has fallen through the media and collected at the base.  It was probably as much as a half of a plastic spoon full.  I thought maybe if I doubled up on the coffee filter that it might help,  I tried that this morning and it probably did some but there is still a significant amount at the base.  I am able to get a lot of it out and back into the jar however I am concerned when I go to the next color about them mixing after cleanup.   My question would be IS THIS NORMAL or do I need to get a better brand coffee filter or try another media alltogether?  

this is a great question, I had the same issue recently.  When I made some new cups. My old ones worked fine but I dont remember the brand of filter I used lol.

 

I was going to try 2-3 filters next

I saw on another website that a fellow did a test of different paper products.  He found that 20 and 30 lb

printer paper worked good, while coffee filters were the worst.  He also tried the brown paper bags from

a grocery and they were superior to coffee filters.  We should all test different paper composits and report

back the best findings.

Yes, I am familiar with that same video. His results were based on volcanoes and fluid action in the cup. I was very pleased with the results and had very few volcanoes. I just was surprised at the amount of powder that fell through, I wasn't expecting it at all. I have not heard anyone mention it in previous posts.

I use brown paper bags and vacuum cleaner filters and don't have any paint come through them. 

I have been using coffee filters that I double up. I havent had an issue with powder going down into air chamber. I noticed the 2 coffee filters made a lot less "volcanoes"