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RE: A 9 year old substrate...
Ryan Mills has a problem....
Let's see if I have this right.... 30 Gal tank, set up for 9 years.
Substrate of mulm filled gravel, topped by 1.5" of Flourite, small amount of
laterite + Flourish Tabs in substrate as well. For most of the 9 years,
plantings consisted of Java ferns and Anubias (both of which grow better
attached to rock or wood than when buried in gravel).
Light level is approx. 3 watts/gal (approx. because that 50/50 bulb does
squat for your plants, although it might look good to your eyes).
Low but regular additions of Flourish and an iron supplement are used (is
the iron supplement Flourish Iron???), plus assorted other chemicals to
boost particular nutrients (you mentioned nitrate of soda).
Yeast CO2 via empty canister filter. No external bio-filtration. (How much
circulation is this unit providing?)
> The ph is about 6.8, GH-100, phosphates-.1ppm,
> nitrates-0 (until I added some nitrate of soda),
> temperature-77, kh-unknown at the present time
> (because I haven't been able to get a kit), although
> my buffer was recently tested at 20.
It helps, when quoting water quality parameters, to give the "units" the
numbers refer to - especially when dealing with parameters that can be
expressed in a variety of ways. Your GH reading of 100 for example - 100
what? 100 ppm CaCO3? 100 German degrees of Hardness?Which brand of test kits
do you use? How old are the reagents?
Also, you say you don't know the kh but you quote "buffer" as "20". As
aquatic gardeners, we are concerned with Alkalinity, which is what most "KH"
measuring kits on the market are actually reading. The alkalinity of the
water is what provides the "buffer" against a too rapid or extreme pH drop
when CO2 is added to the water. What are YOU referring to when you use the
term "buffer" and where did you get this reading of 20 (and again, the unit
used would help)?
> I have been using RO Right in the lower recommended
> ammount in distilled and/or Tap Water Purifier water.
> 5 gallons are changed a week to keep down phosphates.
Kent Marine R/O Right is, according to a source I know and trust, a
repackaged version of their marine salt. I've used it for several years.
What water source to you use for "top up" water? When water evaporates, the
salts in it get left behind. If you just keep adding water with more salt in
it, rather than using distilled water (or occassionally "flushing" the tank
via a series of larger water changes), over the course of 9 years the water
in the tank might get pretty saline.
Why do you have to resort to reconstituted water? What's wrong with your tap
water? Do you KNOW that it has high Phosphate levels (via a reliable test
kit or from information from the water utility)? It is usually easier to
learn to deal with the devil you know (your tap water) than the devil you
don't (the reconstituted water), unless you KNOW that there is something in
the tap water which would preclude it's use in an aquarium.
> Plants are Heteranthera zosterifolia (the fastest
> growing plant ever), Hygrophilia polysperma and
> difformis, Rotala marcandra and wallichi, Bacopa
> caroliniana, E tenellus, Hydrocotyle leucocephala,
> java fern, Limnophila sessiflora, a nymphea lotus,
> Myriophylum sp, a bit of Liliopsis, and some
> Aponogetons.
How MANY plants are currently in the tank? What was their condition when
planted and how long after planting did symptoms of deficiencies show up? If
you uproot a plant now, what is the condition of the root system? Do you
know if the root systems of your plants are all contained within the 1.5"
Flourite layer of the substrate, or do healthy roots extend down into the
older layer of mulm filled gravel as well?
> 1. calcium deficiencies. My tenellus leaves continue
> to look chalky and sometimes bent a bit after trying a
> variety of calcium suppliments. I've tried calcium
> chloride, gluconate, and hydroxide. None make a
> difference.
Then your problem wasn't a Calcium deficiency. Diagnosing nutrient
deficiencies without access to a full lab and years of experience can be
"iffy" at best. The easiest way (for an aquarist) is to add (just) the
element you suspect might be missing and monitor the results - if the
problem is corrected, your guess was correct, if it continues, the element
in question was not deficient in the first place. Many deficiencies share
similar outward "looks".
> I recently tried a very small ammount of
> a Kent marine buffer that I at first thought to
> contain calcium carbonate. Then I realized it has
> carbonate, bicarbonate, and other salts of magnesium,
> boron, and potassium, but not calcium.
In my tanks, and with my water, Calcium and Magnesium are best maintained
using marble or limestone chips. In the presence of carbolic acid (CO2 +
water), sufficient calcium and magnesium ions are dissolved into the water
to suit the plants. Exotic chemicals of unknown composition designed for
other applications are best left in the hands of qualified chemists (which
I'm not).
> source for it? My buffer had been tested as zero
> before the addition of the Kent stuff.
Again, this term "buffer" comes up! What "test" are you speaking of? The
best "buffer" (Alkalinity builder) for a planted tank is baking soda (Sodium
Bicarbonate), sold in every grocery store.
> Will the
> calcium carbonate help that and prevent the ph from
> going down too far?
Calcium Carbonate (CaCO3) or limestone (CaMgCO3) will affect BOTH the Total
Hardness of your water (by increasing the number of calcium and/or magnesium
ions dissolved in the water) AND the Alkalinity of the water (via the
carbonate portion, which will convert to the bicarbonate form).
> Will the leaves be greener and
> straight? I got some macrandra at an auction that had
> very small leaves, but the new ones are normal looking
> (NOT indica). I don't understand why this plant is
> actually improving while the tenellus is looking
> worse.
Get used to one fact - sometimes you can't grow EVERYTHING you might want in
a particular tank. (That's an "aside", B.T.W., but one that most experienced
people know only too well.)
> 3. Too much space between the nodes on the Limnophila
> sessiflora and Myriophylum. I have 3 watts per gallon
> of good light. Isn't insufficient light a cause of
> that?
Insufficient light of the right type is possible ONE cause of that growth
pattern - there may be others that I'll get to shortly...
> I would think the 50/50 would give enough blue light
> to keep things bushy.
The Vitalights should provide enough light of the correct spectrum to keep
things bushy, provided that all other growth factors are being met. You
don't need to use exotic bulbs designed for marine algae in a freshwater
tank. The use of actinic bulbs is meant to simulate the absorption of the
red wavelengths of light by a deep layer of salt water. Freshwater plants
are native to depths of under 20 feet - where most of the sun's spectrum is
quite capable of penetrating.
There are still too many unanswered questions to be able to give you a
definitive answer to your problem, but I "suspect" that the root of your
problem might lie underneath your Flourite. No substrate is capable of
supporting good plant growth indefinately, especially if it is not a good
one to begin with. A plain gravel substrate which lacked, for many years, a
good number of healthy growing roots (which can pump water and oxygen into
the substrate) might, after 9 years, simply be no longer capable of
supporting good growth. Mineralized fish "poop" makes a wonderful plant
food, but 9 years worth of the stuff might be too much of a good thing - the
lower layers of your substrate might be a toxic waste site, leaching toxins
into your water column.
Notice that above I said "might". I don't know - and unless you uproot a few
or your plants and examine their roots, neither will you. If you find that
the plants currently in the tank are keeping their healthy roots mainly in
the Flourite layer, then you probably have no choice but to break the tank
down and was the gravel (you should be able to re-use it, once you have
washed it well - the toxins will wash out).
James Purchase
Toronto