If it's not a pectic haze, I'd use sparkolloid. I have 1 out 3, 5gal. apple wine carboys that has not cleared as well as the others. At only 4 months old I'll wait another 2, but if it doesn't clear by then I'll hit it with the sparkolloid, it's always done the trick in the past. I have also [like Wade] used it on a stubborn Peach Wine. Again it was only 1 out of 3 carboys, sometimes I think it's the last carboy that was racked off the bottom of the 3 primaries is the hardest to clear. I usually rack 1/3 of each primary into 1 carboy. May change system so the bottom of 1 primary only goes to 1 carboy with a middle 1/3 & a top 1/3 of the others. Roy