The reason that bare bottom tanks work is for a couple of reasons.
First, while a DSB
is a natural Nitrate reducer, LR
will eventually take over the job for nitrate reduction over a period of time. Those tanks I'm seeing with zero nitrate and bare bottoms tend to have massive amounts of healthy LR
and/or be very established. Just like ammo/nitrite reduction, the bacteria that take care of nitrates soon will migrate to the most efficient location, which is logically where nitrites are being consumed, and that should be inside your LR
. It's usually the guy with the 4month old tank, 150lbs of showcase Fiji LR
, and a couple inches of CC
that is doing the most complaining about high nitrates.
While I use DSB
's on my tanks and also have nitrate levels that can barely be detected, I'd yank them in a heartbeat if I knew my LR
was ready to take over. An inch of substrate is fine with me, looks good (better than bare glass), and isn't deep enough to be a toxin sump.