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Steve's nutrient method (derived from Krombholz)
> But that's a completely different subject. This thread started with a
> question on _my_ methods. A general query was also sent out for other
> people's methods, but let's retitle that thread so my name isn't on
> the top!<g> Why don't you write a quick synopsis of the method you
Did you say quick synopsis? from me? ok you asked for it. ;-)
Ok, in synopsis form here it is. One of these days very soon, it's my
goal to write this up in a more detailed form. By the way, this method
is freely adapted from Paul Krombholz's methods; I just added a few
tricks here and there.
Step 1) read as much as you can stand. The Krib is a good starting place
especially for lighting and CO2 topics. For nutrient issues, its
probably too confusing. The TAG back issues with subjects on nutrients
and soil substrates are excellent. Any posting here on the APD by Dave
Huebert or Paul Krombholz on nutrients are excellent. My substrate
article on my web site is also good background for understanding the
theory and mechanics of substrate nutrients. See
Step 2) get a new tank or sterilize an old one using household bleach.
Also sterilize any old filters you plan to reuse and any other fixtures
that go into the tank that may be hosts for filament algaes. BTW,
soaking plastic in bleach overnight is not a good plan; it becomes
brittle and cracks. 10-15 minutes in a dilute solution after you've
scrubbed it clean is good enough. Or just buy all new stuff; its easier.
Step 3) deal with the lighting and CO2 hardware issues (this is about
nutrients so we won't cover those topics) Do this in advance because it
takes a long time to get everything together. But don't turn the lights
on yet. Don't buy fish or plants yet either.
Step 4) find your water utility in the phone book and call them up for a
water analysis. You want to know the concentration of potassium,
magnesium, calcium and if there is a significant amount of nitrate or
phosphate in the water. Excess amounts of copper or lead are good to
know about too.
Step 5) install a bottom layer of subsoil preferably with clay in it
into the bottom of the tank. 1 or more inches is good. No organic
materials in this layer.
Step 6) prepare a mixture of Krombholz soil soup (mix with water to form
soupy mud) and strain this through a screen to remove the fibrous
organic material. Use garden soil for this that you dig up yourself, not
from a nursery or potting soil since it almost certainly contains too
many nutrients. Bagged earthworm castings is way too rich to be used in
large amounts but the adventurous might add 2-4 cups of it to the
Step 7) dry the mud or let it settle to remove as much water as possible
and mix this 3 parts to 1 by volume with sphagnum peat moss. The magic
ratio is 20 parts dry weight of soil to 1 part dry weight of peat. The
soil provides many nutrients including all trace nutrients as well as
nitrogen and phosphorus. The peat is necessary to keep the substrate
redox potential low enough to ensure that sufficient iron and manganese
Step 8) mix a couple of handfuls of dolomite lime, ground up egg shells,
crushed coral or sea shells to provide a source of calcium and magnesium
which can slowly leach from the substrate. This is insurance against a
shortage of calcium and magnesium which are preferentially absorbed from
the water by aquatic plants.
Step 9) make a 1" layer of this peat and soil mixture over the subsoil
layer in your tank.
Step 10) cover the soil layer with a layer of 1-3 mm fine aquarium
gravel. Use brand new, unused gravel only.
Step 11) add water and let it sit a few days. Now would be a good time
to test for ammonia, nitrates and phosphates. If the nitrates or ammonia
are above 50-100 ppm and the phosphates are also very high, your
substrate is probably a little on the rich side. You can always expect a
fairly sizeable amount of nitrate in the form of ammonia to be released
from a labile substrate that contains decomposable organic material.
Peat and subsoil do not release too much nitrates or ammonia so this may
be preferable. Peat does however tend to release a fair amount of humic
acids and floating debris. The humic acids will make any CO2 or pH based
hardness measurements impossible or difficult. It's a trade off; you
want the iron to come from your substrate so you need the peat. Peat has
other nice benefits however such as improving pH stability and
inhibiting bacterial growth. You will also need some form of filtration
to remove floating detritus from the water to keep it clear. This is
especially important for the first couple of months to catch peat
Step 12) replace all of the water. This can be repeated a few times if
the soil is too fertile but it may take a week or two for it to decline.
You have the option of growing green water and feeding daphnia or
growing BG algae and feeding it to snails as a method to harvest and
remove the excess nitrogen and phosphates from the system. With a low
fertility soil, such as subsoil, the problem of initial nitrate and
phosphate release is minimized but later you'll probably need to
supplement these. Avoid an overly fertile (labile) substrate if you are
Step 13) buy some floating plants and fast growing plants such as
Ceratopteris, Salvinia and Hygrophila species. Inspect the plants for
any sign of filamentous algae. If you find any, don't use any of the
plants from that source. Go to antoher source.
Step 14) mix 19 parts water to 1 part bleach and apply a 2 minute dip to
the plants. Rinse well and plant them immediately in the aquarium.
Step 15) Turn on the lights using an 11 hour on 13 hour off timer cycle.
The CO2 should also be working. Snails, and daphnia are good additions
at this time if you have problems with green water or BG algae. If you
didn't rid your plants completely of filamentous algae, you'll need SAEs
and glass shrimps but these cannot coexist with daphnia. They will,
however, deal with any daphnia overpopulation problem you may have. ;-)
If you have soft attached algaes on the glass or plants, Otocinclus are
a good addition. Using the powerhead method, I adjust my CO2 input to
achieve 1 bubble every 4 seconds and use a 6-8" half inch extension on
the powerhead outlet to increase efficiency. The powerhead also
stimulates water circulation which assists the plants to obtain CO2
through the Prandtl boundary layer. It also helps to prevent BG algae
from forming. Snails are very good for eating blue green slimey
Step 16) using the water utility analysis, calculate how much calcium,
magnesium and potassium you need to add to achieve 60 ppm calcium, 5 ppm
magnesium and 10 ppm potassium. Calcium is dosed at double the dosage
initially because the peat seems to soak it up for the first month or
so. Later on you will adjust the dosage to achieve 30 ppm calcium, 5 ppm
magnesium and 10 ppm potassium.
Step 17) if you had no ammonia or very little during the initial week of
water without light, chances are your nitrogen levels are very low. Dose
to achieve 10 ppm nitrate ion.
Step 18) replace 20-25% of your water every 1-4 weeks. Add only enough
nutrients to the water to achieve the target dosage for the replaced
volume of water. THIS STEP IS CRITICAL. Only add nutrients when you
change water. It doesn't seem to be important how often you change the
water; I can stretch it out to a month without any obvious problems.
**** REMEMBER, if you replace 25% of a 50 gallon tank which amounts to
about 10 gallons of water (allowing for substrate), then base the
nutrient dosages on the TEN gallons, NOT 50!!! ****
Step 19) after any initial algae problems are solved, remove any excess
plants from the initial planting and replace them with what you want to
grow. Always inspect for filament algaes. Plants with relatively large
leaves such as Cryptocorynes, Echinodorus, Hygrophila, Java Fern,
Anubias, Bacopa and Ludwigia can easily tolerate a 4 minute bleach dip
which will kill any type of filament algae. 3 minutes is good if the
plants came from somewhere that had no visible black brush (red) algae
or coarse hair algae. If you suspect those algaes, use a 4 minute dip.
Delicate plants like Rotala macrandra or Heteranthera zosterifolia need
about a 2 minute dip. This will kill the fine furry algaes like
oedogonium. Never put any plant into the aquarium unless it has had a 2
minute bleach treatment or it came from an aquarium YOU know to be
sterile of filament algaes.
Step 20) add a few more fish. Avoid big ones that will create problems
with the amounts of food they consume and turn into fertilizer. Fish I
like are Cardinal Tetras, Neons, Swordtails, Otocinclus and glass
shrimp. For Killifish, its best to setup a species tank. Never add
water from foreign sources that come with the fish. Instead put the fish
into a bucket of aquarium water to acclimatize and then net them to put
them into the tank. Look at the water closely for any algae filaments;
do not allow these into your tanks. Paul Krombholz even quarantines fish
for a few days to allow algae in their digestive systems to be excreted.
Step 21) if necessary only, (i.e. floating plants grow poorly),
calculate the amount of chelated Fe to add to achieve 0.1 ppm and add
about half this much. Do this rarely, like once a month but if
everything is growing fine, skip it. It tends to cause spot algae to
grow in my tank especially if I use anything close to recommended
dosages. Of course I use strong MH lighting so with less intense
lighting this will probably not be a problem. Note that chelated
nutrient dosing is virtually eliminated with the use of peat and soil!!
Algae is really at a disadvantage if there is no chelated iron in the
water. Peat however, releases humic acids which also act as natural
chelators but there doesn't seem to be enough iron in the water from
this to cause algae problems.
Step 22) check your plants for nutrient deficiency symptoms and adjust
the dosing appropriately.
Step 23) for heavy feeder plants like Sword plants (Echinodorus) or
Crypts, you can add pieces of Jobe's fertilizer sticks near the roots to
provide nitrogen and phosphorus. You can also prepare clay balls
impregnated with slow release fertilizer pellets like Osmocote. Under
high light conditions, it is often necessary to supplement nitrogen
(assuming everything else is in good supply)
I'd like to get Paul Krombholz and a few others to check over what I've
written so far for accuracy. I'd also like to explain the common
chemicals you can use, how much to use to achieve a specific dosage, a
recipe for creating your own nutrient formula and where to locate
chemicals. At that point, this should become a very useful guide. As a
very rough guide, 1/8 tsp in ten gallons of many of the chemicals will
give you around 10 ppm. That works for potassium sulphate (K), epsom
salt (Mg) and calcium carbonate (Ca). If you have an accurate scale, the
periodic table of elements and the chemical formula, you can easily
calculate doses for any compound. I have tested most of the steps in
this procedure except the 1-2 week dark period to remove nutrients from
the soil. I usually just go straight to plants right away. Paul and I
are using a higher ratio of peat to soil but my feeling is that we don't
need so much and its releasing a lot of humic acids. I also have used
micronized iron and trace element supplements however I cannot determine
at this point if these additives are beneficial or not.
Sorry for the long post! Hope it is useful. :-)