In one of my planted established tanks, I vacuum once a week, this is the
only water that is replaced, about a 2 gallon [imperial] bucket full, [rain
water] The tank only has UGF's and no external filters are used,, The tank
houses Angles, and a few neon Tetra's. I really believe that tanks maintain
a balance given the chance..

bassett


wrote in message
om...
(Harry) wrote in message
m...
I am fairly new to the planted aquarium community, so please solve
some incongruities, if you could.

When I had just plastic plants in my aquarium, I was told to change
15%-20% of the water every week because of the build up of Nitrates in
the water. The idea, as I understood it, was that there is bacteria
that will take the ammonia produced by the fish, and make it into
Nitrite, and there was bacteria to take the Nitrite and turn it into
Nitrate, but that there was nothing that could really be done about
the Nitrate.

Now, I have seen that Nitrate is beneficial to plants, to the extent
that people seem to get fertilizers to *add* Nitrate to their
aquariums. Those same people seem to advocate changing their aquarium
water from 30%-50% (!) weekly/every other week.

It seems like a planted aquarium should not require very many water
changes, and almost no vacuuming (as fish waste is something that
plants like!). Am I mistaken, here? What is the reasoning, with a
planted aquarium, to change the water? Or is my understanding of the
chemical/bilogical processes involved mistaken?

Thanks!

-Harry

Perhaps the best utility in keeping things stable is doing frequent
water changes. This prevents any thing from building up.
Dosing nutrients 2-3x a week will keep things from running out.

This is a very effective method for folks with CO2.

It allows you to re set the levels in tank for at least 50% of the
water(say if you do a 50% weekly water change).
This can be dosed to within 1-2 ppm of NO3 for example with a teaspoon
from dry powder. Few test have that accuracy
Fish/plants like water changes, algae generally does not.

Non CO2 tanks want the opposite, the levels of nutrients added are
solely from the fish/food/substrate. So you do no water changes for
3-6 month(and then mainly for after a large pruning etc), The rate
exceeds the fish waste etc in the CO2 enriched tank. So folks need to
dose KNO3 etc. You can test each time and dose accordingly or you can
do a water change that you are going to do anyway(does 20% take longer
than 50%? not much) and add a known amount of KNO3 etc back and this
yields good accuracy and results.

This prevents a deficiency before it happens by maintaining good
nutrient levels all the time. It's easier than testing for most folks
and cheaper.

Why the obsession not to do water changes eludes me. But if that's
your game, do the non CO2 plant tank route. Don't mix these two
methods together. Be clear about this. Folks m ixing these two up
often causes confusion and differences on responses on the web. I
don't do anything really to my non CO2 plant tanks, some plants don't
make it etc, but the tank looks nice, the growth is slow etc.

The CO2 tank gets weekly water changes etc. It looks nice and the
growth is super. Depends on what you want to do.

Regards,
Tom Barr.