There's still homes in Louisiana that have blue tarps on the roofs to stop the water. It should work well for you in the short term. De

I always cover my germinating seed with a plastic cover. I save plastic carry-out containers with clear lids for that purpose, and plugs get set into a Perma-Nest tray with plastic lid. The lids keep things from drying out, and I never water anything in the germination tray before they come up (other than preparing the sowing medium, obviously). They usually take maybe a week or so to germinate but obviously some stuff comes up within a few days -- it's fine to leave the plastic lid on for a few days after germination, it will keep the moisture in. Not sure what you use as medium, but IME Jiffy pots are going to dry out a lot faster than a potting mix. That said, I'm curious why you start peppers and tomatoes so early? Planting out time isn't until mid-May at the earliest and really it's best to wait until the last week of May because mid-May is iffy -- you're in OH, so thinking it is similar down where you are - ?. Are you using season extenders (e.g. wall-o-waters) to set stuff out in late April/early May? If not, sowing when you return at the end of March should be fine, you'll still get 6-8 weeks indoors, that's plenty of time for peppers and tomatoes.

For that application, I’d consider a hardwax oil, but only if you want a matte finish. One example is Rubio Monocoat: super easy to apply (do all sides), and smells wonderful, but sand carefully/evenly and only to 120 grit (150 at most), or you’ll have trouble with adhesion. https://www.rubiomonocoatusa.com/pages/oil-plus-2c-colors

I installed then a water softener hoping it will solve the stains issue. They still show up. I find myself drying everything to reduce seeing spots. I was told then that’s because I have high tds level - almost 600 this is the cause for them showing up. I was hoping someone would give me a tip on how to clean off these spots.