Green mucous & Black Fungus in Ear

Where to start? My son has had an ear infection since August 3rd. Since then he has been on 4 rounds of antibotics (amoxicillen & omniceff) plus Ciprodex ear drops. A CT scan was done on pre-op day -- found extensive fluid in the inner ear space, small amount of erosion on the top bone above the anvil, stirup & hammer area. Sept 22nd surgery was done to clean out the ear. Tubes were placed. Within 3 days he was still in pain & the ear felt "gunky". Took back to ENT office only to find more fluid was present in outer ear canal. ENT filled canal full of antibacterial/antifungal powder to help dry up the ear. Next weekly visit they suctioned out a huge green mucous thing along with black fungus along with the tube that had fallen out. My son said instantly it felt better. Once again filled w/ the powder to help dry it out. Went back 3 days later ear is better but still not 100%.ENT stated that the tube looked clogged (I told him that it fell out last week in the office) So there is now white mucous where the tube was. Now after 8 days I can see more mucous in that ear. At this point I am losing trust that the ENT knows what to do. He states that this is a very hard thing to clear up once it starts. It all started when his plugs fell out while swimming this summer & pool water got behind the ear tube in the inner ear. Does anyone have any suggestions at all? We are looking into a second opinion. HELP!!!!!

[Caryopteris]

Stop dairy foods and have him checked for Celiac disease.  Just stopping dairy will likely clear it up though.