Hi Daniel,
Definitely do not drink green tea because it has caffeine in it and caffeine can relax your Lower Esophageal Spinchter (LES) as well as irritate your stomach lining. If you're going to drink ice-tea make sure it's caffeine free and preferably organic as pesticides / herbicides/ etc. can cause problems inside your digestive tract.
When I drink water I drink it in small amounts. I also drink coconut water, again, in small amounts at a time. I also make homemade ginger tea out of organic ginger root and I also drink organic chamomile tea.
I drink all liquids in small amounts because the stomach isn't very smart. I notice when I drink large amounts of liquids (for me a large amount is anything over 4 oz) my stomach reacts by releasing more acid, so I drink it in small amounts.
Here's a trick that I learned from my current nutritionist about
10-15 minutes after each meal I peel an organic red apple, core it, and slice it up into slices. I then eat 2 to 4 slices. Apples, despite their low acidic content, are very alkaline and also contain enzymes. In some people they help with GERD symptoms and digestion.
I'll also eat a peeled apple slice after I drink liquids sometimes. It all depends on how my stomach is feeling.
I use my juicer to make carrot / celery / apple juice and that's a combination my stomach seems to like. I stay away from all dairy drinks and soy-based drinks. Almond milk and Flaxseed milk are tolerated pretty well though.