Bo0ger1, show me your tank...

"bo0ger1" .@. wrote on Thu, 30 Nov 2006:
I now have a pulsing xenia (new edition last weekend)
Does this qualify as a reef tank now?

Yes, that's a start. But it's now a very new reef tank.

We'd be much more interested a few years from now, and after you've added
some stony corals (acropora, etc.). Those are the ones that appear most
sensitive to "water quality" (whatever that might mean), and that are rumored
to benefit most from water changes.

Your "no water change" strategy will be much more impressive if you can grow
stony corals over many years.

I don't undestand what the big deal is, here? We all know that a Yellow
Tang places less demand on a tank than a Spanish Hogfish. I'm just trying
to get a better idea of what sort of bacterial demand your fish place upon
your NWC system.

Why is this relevant? If you truly understood the nitrogen cycle and
denitrification you wouldn't be asking this question. ANSWER: If my
bioload was in excess of my bacterial metabolic capabilities, wouldn't my
water tests signify this? AGAIN, bacteria fluctuate in population directly
with their metobolic "food" source. More "food" and they grow in number (in
general). Why are you having trouble with this?

You've been asked this question many times, and you avoid it each time.

Yes, we know that the bacterial population depends on the availability of
food. And that, as you slowly add bioload, you slowly get more
denitrification ability.

Yes, we know that there's a limit to the amount of bacteria you can grow,
and excess bioload will show up in your various nitrogen tests. Since yours
are clean, clearly your bioload is below this limit.

But there is STILL the question (which you haven't answered) about what your
bioload actually is. It's not very impressive to have a couple tiny fish in
a huge tank, and then claim that "you don't need water changes". We're much
more interested if you stock your tank as densely as most reef hobbyists, and
still get good water parameters with no water changes.

Why is this hard for you to understand? An important part of your claim
(that water changes are unnecessary) must surely include the maximum bioload
that can be sustained with that approach.

Why do you refuse to answer the question of what your bioload actually is?

Want to lower your bacteria cell count even further? Increase the
percentage of water you change. What do you think would happen to your
bacterial cell count if you hypothetically changed ALL of your water with
every WC?

Not much. The majority of denitrifying bacteria is probably in the rocks and
sand, not in the open water column. You seem to be suggesting that if you did
a 100% water change, you'd eliminate all the helpful bacteria, and it would be
like a brand new tank that you would have to cycle again from the beginning
(to grow all the bacteria from scratch).

This is completely false. The bioload capacity of a mature tank is more a
function of the amount of (surface area of) live rock and sand, not so much
the number of gallons of water.

You can do a 100% water change without greatly affecting the denitrifying
ability of your tank.

-- Don
__________________________________________________ _____________________________
Don Geddis http://reef.geddis.org/
If you make ships in a bottle, I bet the thing that really makes your heart
sink is when you look in, and there at the wheel is Captain Termite.
-- Deep Thoughts, by Jack Handey