Hi Adam,

(A response on this NG told me it should be 50/50
Fluorite/gravel, which I guess I'll stick too.)




100% Fluorite is even better, but of course more expensive.



I have a 20w Tunze substrate heater.



I don't know about that particular one but I have heard a lot of people say
their substrate heaters didn't last very long. Mine lasted only a few weeks.
I suspect substrate heaters are of no real benefit to a planted aquarium
where the whole bottom is covered with plant routes anyway.
--
Regards,
Marvin Hlavac
Toronto, Canada