That Black Line Around Your Tub Isn't Just Ugly — It's Eating Your Wall

See that dark line where your bathtub meets the tile? In Florida's humidity it's not a matter of IF it turns black — it's WHEN.

Here's what most people get wrong

1. ❌ Bleach is not a fix. It just whitens the surface — the mold lives INSIDE the old caulk, and the black comes back in a few weeks.

1. ❌ Caulking OVER old caulk is a trap. New silicone won't stick to the old layer. It peels within months, and water keeps getting behind it.

1. 🔧 The real fix takes a bit of work: cut out ALL the old caulk (every bit of it), let everything dry completely, then lay one smooth bead of 100% SILICONE — "kitchen & bath" type. Not paintable acrylic — in wet zones it fails fast.

Here's the part nobody wants to hear: if the caulk is cracked or peeling, water is already getting BEHIND the tub — into the drywall or backer board. Leave it long enough and a $30 caulk job turns into rotted wall, hidden mold, and a repair that's ten times more expensive.

⚠️ Red flags that mean it's already serious

• The caulk crumbles or pulls away when you touch it
• The wall around the tub feels soft or spongy
• A musty smell in the bathroom that never goes away

Florida bathrooms never really dry out. Check your caulk every few months — catching it early is the cheapest repair you'll ever do in this house.