I picked up a 5lb block of Amaco Red clay from Micheals last night for 10 bucks, is this the right stuff to use when making Mineralized Topsoil?

That is the right clay to use in the aquarium...the 5lb block will last years.

you live in Arizona...dont you all have red clay everywhere outside?

Actually I played around last night using good ol arizona dirt to see if i could get the right slurry, it worked really well. I actually use it every year in my pond, all my pots are filled with arizona soil, which is very lean in organics, plus pond root tabs and never had algea issues.

As for the 5 lb block welll......... after i use what i need my 2 year old gets the rest, it will not last long :-D

i was afraid to add the amaco clay i bought, because it smelled like a hospital

I bought the same stuff and haven't gotten to it yet. I have heard conflicting things about Amaco clay, might not use it...

Its listed very specificly as non toxic, thats a good indicator to me

So is silly putty, but not sure I would want to grow plants in it, lol

Natural clay should smell like fresh dirt. Sometimes good, aged elastic pottery clay can have an organic funky smell, but that's only after us potters have messed with it and aged it for awhile- fresh out of the package should have absolutely no chemical smell. By chemical I mean alcohol, petroleum, or that type of odor.

This doesn't mean if you can't smell chemicals that it's okay to use- just that if you smell chemicals- DON'T use it.

And I'm chiming in as a clay expert, NOT an MTS expert!

There was a funny smell when I opened the package but I was not sure if it was the clay or the plastic it was wrapped in, smelling IN the plastic wrap had far less smell.