I haven't seen anyone respond, so I guess I'll take it.
** Disclaimer: I work for Pall Filtration, but none of this is a sales pitch ****
By canister filters, I assume you mean "stick" type filters. The filters you get for your water system can be used for beer, however, they are different. Depending on where you live, your incoming water is probably pretty good, so the filter doesn't have to work that hard. Not so with beer. Also, beer will flow slower and put more pressure on a filter that water will. Lastly, a number of home water filters have carbon to pull out off-tastes. You obviously don't want a filter that takes out the flavors you have worked so hard to put into your beer.
I have seen a number of small breweries use stick filters for small batches. Just be aware that once you get to a certain size batch, it becomes more cost effective to go to P&F, Lenticular, or DE.
There are too many variables to list here, but if you need more info, please feel free to contact me at Milton.Leland@Pall.com