Portable water filters for fluoride-how to install specialty cartridges

Hi, it's been awhile since I ordered replacement candles for my GSS-Mini. Is the 2.75"x5" (L) Imperial SuperSterasyl ATC ceramic candle the replacement for the old 4" candles?

The important thing is that it filters out Fluoride and heavy metals.

The 5" ATC does go in the GSS-Mini and it will filter out particulate, chemicals, microbes, and lead (should reduce some other heavy-metals as well).
It should not be relied upon for fluoride removal (thought it may reduce levels).  Fluoride requires a separate/dedicated specialty filter that can be added on to a system, but because of its' size, the GSS-Mini can not hold this additional element.

Thank you for your response. I've been using the GSS-Mini since 2006 and I was told  that it does filter out
fluoride. In any event, I don't test my filtered water beyond knowing that it tastes worlds better than water
straight from the tap, and I can drink it all day without feeling queasy. Plus it's yet again worlds better tasting than any "purified" water I can buy at the store.

I've looked at your other filtration systems, but I live in an apartment and the management here won't let me modify the plumbing in any way, so I don't see anything other than the GSS-Mini that I can use. But maybe I missed something that you have. Do you have a product that can completely filter out fluoride, and hopefullypharmaceutical drugs as well, that doesn't require any kind of modification of household plumbing? If not, I'll be quite happy to continue using the GSS-Mini.

The media used in the ATC filter can remove lead and reduce the levels of other heavy-metals (fluoride is considered a heavy-metal), but should not be relied upon for fluoride removal.
For apartment I would recommend the GSS2 portable filter plus 2 x CN-B2 2"x4" fluoride/heavy-metal filterelements. I'll provide the link where you can purchase these items:
http://doultonusa.com/HTML%20pages/portable_systems.htm

Using this set-up, the fluoride and pharmaceuticals will be significantly reduced to near non-detectable levels.

I received my GSS2 water filter w/specialty filters today, and just to make sure before I use it, do the fluoride/heavy metal specialty filters go in the (bottom) clean water receptacle? I don't see anywhere else for them to go. If so, should I be careful not to let the bottom fill to the point that the water would contact them? It seems like eventually the specialty filters will get dirty, and then they would contaminate the clean water, but I don't know how these work.
Also, can these filters (all 4) be scrubbed clean with a Scotch Brite pad, like the GSS-Mini's can?

The B-2 elements attach at the underside of the upper chamber, just as the Installation Instructions of Specialties Elements for Gravity Filters sent indicate. You are correct to assume that they hang in the bottom chamber. They can be in contact with the water, for they are water filters which are designed to be in contact with water at one point or another. They would be in contact with already filtered water so they should not get dirty. However, if the filter go for extended periods of non-use, you would be advised to clean all the filters and canister, and discard a batch of water before continuing to use filter.
Only the ceramic filters should be cleaned using a Scotch Brite pad.