To water change, or not?

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

Harry wrote:
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?

This question pops up every so often in this group. There are plenty of
opinions and arguments on both sides of the water changing issue. I don't
change nearly as much water as some folks do. Perhaps 10% once a month in
the big tank. The small tank gets more changes because its plants are not
as well established yet.

As always, YMMV. Just try it and see if it works for you.

--
Victor M. Martinez

http://www.che.utexas.edu/~martiv

"Harry" wrote in message
...
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

In a healthy planted tank, the changes aren't to deal with Nitrate levels,
but to add trace elements that would otherwise be lacking and are not
typically added as a fertilizer. There is probably a way to find all of the
trace elements you would ever need and dose them carefully (based on current
levels) and obviate the need for water changes. This would be terribly
complex however!

Water changes are really a simple way of removing what you have too much
of (micro and macro) and adding what you have to little of (on a micro
level). To handle the lack of something on a macro level (Potassium, Iron,
etc..) you'll need a Fertilizer.

Rod

Water cycles through natural systems, and aquariums are much smaller
than even tiny ponds. So it makes sense to change the water, but I agree
25% weekly may not be needed. That is of course if the fish load is low.

Chris

Harry wrote:
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

"Rod Runnheim" wrote in message
...
In a healthy planted tank, the changes aren't to deal with Nitrate
levels,
but to add trace elements that would otherwise be lacking and are not
typically added as a fertilizer. There is probably a way to find all of
the
trace elements you would ever need and dose them carefully (based on
current
levels) and obviate the need for water changes. This would be terribly
complex however!



So... on average- how much how often?


--
Toni
http://www.cearbhaill.com/aquarium.htm

"Toni" wrote in message
link.net...

"Rod Runnheim" wrote in message
...
In a healthy planted tank, the changes aren't to deal with Nitrate
levels,
but to add trace elements that would otherwise be lacking and are not
typically added as a fertilizer. There is probably a way to find all of
the
trace elements you would ever need and dose them carefully (based on
current
levels) and obviate the need for water changes. This would be terribly
complex however!



So... on average- how much how often?


I typically change between 15% and 20% every two weeks. I tried to get
away with less than that for a while, but the plants started to suffer.
A lot of this depends on your plants growth rate -- Very fast or very slow
and you may need to change more often or in larger amounts.

Rod

(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.

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.