I use the excellent hydrometer sold by Midnite and other vendors. Unfortunately, its little vinyl tube is only affixed with a pressure fit, and tends to fall off. I've now lost two such tubes (about .25" o.d. x about 4" long) in two different cells of my battery bank, and they're proving impossible to see, let alone retrieve. I've always been fastidious about keeping my battery compartment clean and minimizing contaminants in the cells. So the question is...will these hunks of vinyl damage the cells they've drowned in? Thank you.
Since vinyl is a non-conductor and AFAIK does not dissolve in sulfuric acid, I don't think it would make any difference. It might may make a small lessening of capacity at the point of contact between the lead and vinyl, but that would be very minor.
I wouldn't sweat it, but do try to find a more robust device for the future.
Use only plastic & NON metallic items in the cell to retrieve .
I used my battery turkey baster to remove the acid & then the little snake showed up , used a plastic pipe cleaner & got it out. Then I used very thin (.010) aviation inconel tie wire to make a clamp on the tube .
VT