Making base rock

Hi im making the base rock for my tank build and I was woundering if its safe to use portland cement type I? I called all the lumber stores and cement places in houston and everyones carries either type I or II I cant find III

 

http://www.3reef.com/forums/live-rock/make-your-own-live-rock-47495.html

this is all i could find for you but people use type 2 from the research and type but never type 1, hope that helps

 

check out threads by Homegrowncorals, I believe he makes his own

 

I tried going down this path. I'm pretty good at working with my hands, and I made some nice looking rock. The problem is that it takes FOREVER for the Ph to drop. I was really looking forward to making some nice, custom shapes, but I gave up and went with Marco Key Largo rocks instead.

 

Type 2 would probably be better =) I work in the Building and lumber department at The Home Depot, they carry both a 94lb bag and 47 pound bad, you could do alot with the 94lb bag and its around 9$ i think, my 2 cents

 

Thanks for all the replies. Well I drove all over town today and found no type III. I got to thinking and remembered who I originaly got the idea from, ipsf. I emailed him and he adviced me that type I is fine, so I made my rocks. Will post pics when they are done hardening. ;D