You could get a cold-water Plec, I believe they like to clean
the "stuff" off of tanks.

Steve.

--- In tropicalaquaria@y..., "calvan152" <calvan@e...> wrote:
> i have two fantailed goldfish in a 60 litre tank and i get some
> brownish material on the glass,i found a site that told me to clean
> only the front of the tank as this is good for the fish (and the
tank)
> is this true?.i was going to get a cleaner fish but wondered if
they
> would survive in the cooler temps that the goldfish live in or if
> feeders are only for tropical aquariums,also would it be possible
to
> raise the temp in the tank for a feeder and not harm the
fantail`s,at
> the moment i have a heater in the tank but its turned off as the
two
> fish seemed happy at room temp in the small tank i had them in
before.
>
>
> hope you can help
>
> calvan