I'm sorry your dog is having so much ear trouble. I worked for a vet 8 years, and what you describe is an infection perhaps associated with earmites. I have to tell you to take her to the vet. :-) In the meantime, the following may help: put her in the tub, and use a warm, very wet washcloth to clean her ears with Dawn Dishsoap. Get them very wet and soapy. You want it to get down into her ears. when you have it good and frothy, take your thumb and forefinger to massage under/behind her ears where it bulges a bit before meeting her head. Then rinse, rinse, rinse, inside and outside the ear. Rinse until you no longer see evidence of soap. Yes, her ears will have water in them. Thats okay, as she will just skake it out. Dry her ears as good as you can. You can do this as often as twice a week (more than that will not allow her ears time to air-dry enough). Again, I strongly suggest you at least ask your vet if what I have said here is okay, and get her to see him when you can. Blessings - Blu
It may be yeast, possibly caused by the antibiotic killing some of the normal bacteria that would usually keep it in check. I would use a gentle cleaning solution a few times a day. If you can find an OTC solution that also helps dry the ear canal that would be best.
There are a number of OTC natural remedies for ear/yeast problems. My brain is not working right now :) but if you check amazon you will find them.
Good luck!