I would suggest a mildew mold resistant clear caulking , bead width approx 3/16.it will blend and hide deficiencies as well as not stand out and distract your eye from the beautiful tiles

Remove all the old caulking that is in there. Clean it all really well. The clear caulking would work, but, wouldnt be my choice. I would look for a good silicone caulk, that is as close to the color of your tile, as you can get.

I second the motion for color match caulk. My favored tool for removing old caulk is razor blade scraper. Final wipe with alcohol or Acetone.

Thank you! Never done this before. How do I match the color? I mean since can't ake a sample to the store? Any tips? Any special caulk or just regular silicone?

Wow, Klem1 is extraordinary rude. Go to a hardware store with the picture and they can help you. It won’t be an exact match.

It sounds very much like you have not done caulking before. Please watch u tube to learn how to do it, and do it correctly. If it isnt done correctly, you could end up with a bigger problem from water getting in there. As to color matching. Go to the store and look for something that is close to the right color. You may have to even bring a tube or two home, and then exchange them, until you get the proper color. It will not be exact. You just need to be close. Take the picture you put on this post with you. It will help somewhat. Just remember old has to be totally removed, and it has to be totally cleaned. Some caulk, even says on it, that its for bathrooms.

Thank you so much everyone!!! Very helpful!!!!