Ceramic Floor Problem

[Frances L.]

According to my observation, for whatever reasons, the mortar between tiles was not used the right mixture installed …. in between the tiles, there is some mortar and sand above the connection between the tiles.
It catches dirty easy. I consulted with some contractors. They suggested replacement of the floor which I am ready for this costly solution or knife off the dried mixture of mortar above the tiles... time consuming.
I used Oreck Orbiter Multi Purpose Floor Machine to scrub the floor a few times. The outcome was not so promising. .
There is big area to work on (12*13 sq fts). Some time it really bothers me. I am seeking better solution.
http://www.amazon.com/Oreck-Orbiter-Multi-Purpose-Machine/product-revi ews/B004ZP4B60
Any suggestion ?
Thank you for your advice.