With regards to taking probiotics, be careful with them - in some people, they can actually make GERD worse. I am one of those unlucky people. I took probiotics for months and my GERD steadily got worse. I tried stopping probiotics, and things got somewhat better. I also seem to pass blood when I eat Greek yogurt (I am not normally a bleeder). Probiotics help a lot of people, but do keep an eye on it, because they seem to only cause trouble for me!
If Zantac (ranitidine) works for you, you might check with your doctor and see about getting a higher prescription strength dose. My GI has me on 300 mg twice daily, in addition to Nexium once daily. That's been working okay for me. Apparently Zantac is safer to take long-term than something like Prilosec as they are different categories of drug - I don't know the specifics but that's what my GI said, so he is fine with me taking a higher dosage of Zantac.