I've been thinking about my mom a lot lately. It's been almost four months since she died, but I find myself thinking about her more, not less.

If I hadn't been thinking about her, I'd have started when her nursing school graduation picture thudded to the floor from its resting place in the closet. It was night time, and I ran to see what had fallen in my room. And there was Mom, in her white cap, youthful beauty, and steady gaze, looking up at me from the floor outside the closet.

If she'd been able to speak, I know how her sentence would have started: "Tine, you really should. . ."

I had been in the kitchen thinking about avoiding cleaning, just as I am doing at the computer now. Mom disapproved of my preference for reading over doing. And one of her favorite "you really shoulds" had to do with getting California Closets(tm)  to organize my chaos. I suggested that I'd probably prefer to manage the part of the house people actually see first. But she always knew that you have to get to the bottom of the problem if you want to fix it.

But I digress. I'm really here to give you cleaning tips. Or one cleaning tip to get to the bottom of bathtub stains:

ZUD.

When we cleaned out Mom's apartment, I took the under-sink stuff, spray cleaners and an antique power box of ZUD, the Heavy Duty Cleanser. We'd always had it around the house, but I'd never adopted the habit.

So when I thought I'd better clean the tub in preparation for a nice soak after a long and sweaty walk, I decided to give it a try. None of the Scrubbing Bubbles or bleachy things had worked, and even when clean, the tub looked sad.

No longer. ZUD, an old-fashioned mix of oxalic acid, pumice, and quartz, did the job. I think it also polished my nails, as I didn't bother to wear gloves, figuring that any substance found in rhubarb, lambs' quarter, and chocolate (the oxalic acid) couldn't be too harsh.

Of course, I would be wrong about that: ZUD, the "800 lb gorilla of cleansers" is rated environmentally unfriendly. It kills too much bacteria, so you don't want to use it if you have a septic tank. And never mix it with other cleaners, especially those with chlorine.

But if you have an old, stained, porcelain tub, and you just need to feel like you've really accomplished something. . .listen to Mom.