[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: under gravel heating cables



Don Matakis writes passionately about substrate heating, quoting Pablo
Tepoot and Dupla. He obviously likes his cables.

I've had a couple of types of substrate heating and have measured a definite
heating gradient within the substrate (higher directly over a cable, lower
between cables). I don't know if I can say that the tank or the plants
benefited from the heat differential.

But the other "benefits" Don mentioned, quoted from Tepoot, don't
necessarily require nor derive from substrate heating. The upper layers of
any substrate is going to contain more oxygen (be more aerobic) than the
lower layers. This can be caused by simple diffusion from the water column.

In a heavily planted tank with a moderate fish load and CO2 injection, there
really is very little to worry about from Ammonia excreted by the fish. The
plants ought to suck it up as fast as it is produced (I said "moderately
stocked", not a goldfish bowl). The whole Ammonia-Nitrite-Nitrate issue is
really something better left to fish tanks.

What I would like to see is a proper study done using ion probes that are
inserted to various levels within a substrate. Are these "benefits" that
Tepoot and Dupla are talking about REALLY happening in a tank with substrate
heating and missing from one without? Are nutrients made more available due
to the heat? You can "theorize" all you like, but until someone actually
applies available technology to the situation and comes up with reproducible
results, its all just so much advertising copy.

But, as with most things religious, you are free to believe what you wish.

James Purchase
Toronto