I would use caution when using the eraser. I have noted a gritty resdue from them when I have used on dark surfaces. I wouldn't use it in the pool but I see not too much of a problem on the steps if you remove them and rinse very well after cleaning.
PF had a thread on this and someone mentioned that there was a potential problem with the ME and contact with chlorine? I'll see if I can hunt down the info but it was a fairly strong warning NOT to use them in pools - update forthcoming after research.
UPDATE - FOUND THE THREAD!
Thanks to Waterbear, who found the MSDS on the Proctor Gamble site - the manufacturer warns DO NOT USE THE MAGIC ERASER WITH CHLORINE. A chemical reaction that can result in damage or injury.
Okay, well I guess I'll find other usages for my MR. Clean eraser then!
So, how do you keep the scum line from forming, or clean it when it does form at the top of an above ground pool? We started getting this at the end of the season last year and just rubbed it off with a wash cloth...hard going...
I use the Magic Eraser every year to clean the steps, buddy seats, the plastic coping, and the water line of my IG vinyl pool and have not had any trouble at all. I find that it works very well and easy to use. Just used it last weekend when I opened the pool!
In my opinion, the fear about mixing with chlorine is not a concern since the amount of chlorine is relatively low. I would probably not dump chlorine straight from the bottle onto it, but normal cleaning in the pool has worked very well for me.
Just be aware that the Magic Eraser is actually a very fine abrasive. That is how it cleans. It can cause dullness or scratches in some surfaces. It will also break down in the presenced of chlorine but the amount in a pool is very low so it probably is not much of a problem unless you have just shocked.
I have used it for a couple of years in my pool and it works GREAT. Don't worry about using it in the low chlorine level in a pool. Just don't mix it with bleach - that is what the warning is talking about.
Be careful with them, after a number of years they WILL dull the finish and possibly wear off your print on a printed liner.
vinyl cleaners and a sponge work well with removing the black suntan lotion scum line and there are vinyl cleaners made specifically for pools that won't mess with your chemistry - either way, the amount of cleaner you use is so minute in comparison to the grand scheme of things that a couple of seagull turds would have a bigger effect on your pool chemistry.