View Single Post
  #5   Report Post  
Old 14-02-2006, 12:52 AM posted to rec.aquaria.freshwater.plants
NetMax
 
Posts: n/a
Default My tank chemistry readings...how to interpret

"Charles" wrote in message
...
On Mon, 13 Feb 2006 16:47:40 -0500, "NetMax"
wrote:

"ah" wrote in message
. ..
I have used those Doc Wellfish water chemistry test strips a few
times...while I find them somewhat hard to use (some of the color
gradations are too slight for MY eye to distinguish between...), I
seem to consistently come up with the following readings:

Nitrates - 180
Nitrites - 0
Hardness - Very Hard
Alkalinity - 40
Ph - 7.8


So what does this info mean about my tank water quality


Nitrates and no nitrites means the tank is cycled (waste processing =
waste
production). High nitrates (over 60ppm) is usually a sign of poor
maintenance (insufficient water changes) or old tank syndrome (excess
amounts of decaying organic matter, usually in the substrate and/or
filter
systems). If you read up on old tank syndrome, they typically talk
about a
pH crash (from the acidification exhausting the water's buffer).
However in
water conditions where the buffer is high, such as yours (kH of 40 is
very
high, 40dkH?), the symptoms manifest themselves in seemingly
uncontrollable
nitrate levels.

and what
should I do to improve things???


Lack of water changes and old-tank syndrome are both related to
maintenance.
Gravel vacuum, clean the filters, do more frequent water changes. This
will
bring the NO3 levels down. Note however, that an NO3 level of 180ppm
is
basically a thick organic soup, and if you were to suddenly move the
fish
into a zero NO3 environment, the change in osmotic pressure would cause
their gill cells to explode. You will need to make the changes
gradually.

Also, what effect would these kinds
of readings have on plant growth???


We're sure the plants aren't lacking NO3 ;~). Do you have any live
plants
now? I would be curious to know what your general hardness is. With a
kH
of 40, I think the gH would be even higher. There aren't too many
plants
which can do well in very hard water environments, Hornwort and some
Echinodorous come to mind (this group will have better suggestions). I
have
Swords in hard water, but I try to keep it under 16dgH. When my well
seasonally goes to 36dgH, I'm alternating water changes between my
softener
and the well, to keep my total gH down, at the expense of a little more
salt
(which the fish do not mind, but I can't say the same thing about the
plants).

Off-hand, if your hardness is greater than 40dgH, I would suggest you
take a
look at silk plants.

If your hardness is around 40ppm though (about 2dgH) then the situation
changes considerably!!! but since you called it very hard, I suspect
the
former.

I think your pH reading might be suspect. Pour a glass of tap water
and
measure the pH. Then leave the glass on the counter to air a few days
and
then measure the pH again. The first reading is false, affected by the
amount of gases you may or may not have in your water. The 2nd reading
after airing is your true pH. The reading from your tank is your
current pH
(as affected by whatever is in there to affect it up or down). hth



I wondered about the 40 carbonate as well, but I'm not familiar with
that kit.

My water runs GH 55 and one tank I recently tested had KH 5.

For my somewhat hard water, I am growing echinodorous, vallisnaria,
egeria, lilaeopsis, hornwort, anubius, and some things I forgot what
they are. Java moss grows like algae, Java fern doesn't do too well.
Oh, some Cryptocorynes as well.

some of those may be spelled right, I hope I got close.


Spelling looks better than mine ;~). A general hardness (gH) of 55ppm is
about 3dgH (the d is for degrees), or quite soft. A gH of 55dgH is about
1000ppm, probably still a liquid form, but just ;~). The same applies to
kH, 1dkH=17.9ppm kH (iirc).

With karbonate hardness (kH), alkalinity or buffer (all the same thing),
the numbers are less interesting for plants or fish, and more interesting
for pH stability. They recommend a kH of around 5 or 6dkH for good
stability. Less and you're more prone to variations in pH due to
downward influences (mopani driftwood, CO2 injection, etc). A higher kH
and it's more difficult to change your pH downward (which is sometimes
desirable).

hth
--
www.NetMax.tk