We just bought a new tent and the instructions say it should be seam sealed on the inside seam. It also says to apply the seam sealer to the stitching. Does this mean the inside of the fly? If it does, there is already protective tape over the stitching making it impossilbe to apply seam sealer. I ended up applying it to the outside of the fly but it ended up making each seam white (latex in the seam sealer?)
Did I do the right thing?
You didn’t do anything wrong. If the fly was already taped, that will suffice. You just added an element of overkill. I do the same thing. If you’ve ever had a tent leak, you know that there is seldom such a thing as too much seam-sealer.
Taped seams are sealed by the tape, and do not need to have seam sealer applied.
Seam sealer applied to the outside is more likely to be abraded off, so applying it to the inside is the better bet.
Any part of the tent body that is not breathable (i.e., has coated/waterproof nylon) should be seam sealed. Practically speaking, it’s not necessary if the area is unquestionably protected by the fly. I’d seal any floor seams and body seams (in waterproofed nylon) about 6" past (above) the low edge of the fly.