Donald K wrote:

Sir Douglas Cook wrote:


I do have a question for you.
If fish and there waste produce CO2,
Why don't you just add more fish?



The CO2 added by the fish is small compared to levels needed for
"triving plants."

(Which, with even a little thought, means you're in an unnatural
equilbrium, but I'm not gonna go there...)

-Donald

Ah, but thriving plants have a positive effect on the fish I've found -
they help reduce nitr?tes (I can never remember which is the last one in
the ammonia cycle), which means the tank (or at least mine) spends most
of it's time needing very little input from me. I do a water change
every few months, not every other week, for example. No algae problems
these days, no fish problems, everything's healthy, my pair of angels
are breeding in a community tank and raising to free-swimming fry stage
(they're still learning so each batch gets another day or two further
along the cycle before the parents presumably turn into cannibals and
recycle the protein!).

I seriously doubt I'd have a pair of angels breeding in the tank if
there was something nasty going on (not pure wild angels I'll add
though) or the water params were out of whack.

B.P. (Before Plants) it was a constant struggle against algae, frequent
water changes, fish weren't as brightly coloured and I battled with
occasional instances of disease that would randomly crop up (without new
fish being added).

I take the view that the CO2 means I can grow the plants that will
contribute to a better environment for the fish than a purely visual
improvement. I'd much rather add the CO2 (small hassle, small cost)
than go back to battling with algae and much more frequent water changes.

At some point I'd love to go for a completely self-contained system, no
filtration, fish and plants, natural lighting only, etc etc, but then I
realise there's only one way to do that, and that's to Walk Outside ;-)


--


Velvet