Mixing up stock for non-CO2 (maybe Excel) nano-tanks?

[HepCaribou]

I've been sitting on some dry KNO2, KH2PO4, and CSM+B fertilizers (from GW) unused for several years time, but finally want to put it to use.

My aquariums are currently all "nano", ranging from 1.5 gallons (more like 1, with dirt/wood) to 10 gallons. Light is low-to-medium. Non-CO2 (but I'd be willing to do Excel... if it doesn't kill the vals or riccia).

I've just ordered a small electronic scale; I don't really care to measure down to 1/32th tsp for mixing!

To get started, I'd like to work out dosing for my littlest tank -- a 1.5 gallon mini-hex. I just redid it last weekend, but in my excitement neglected that whole *planning* thing somewhat. Light is a twist-in CF "aquarium bulb", substrate is now upgraded to SMS with about 1/4" of Leonardite and a splash of mulm underneath. I forgot to douse the soil in fertilizers to start, however. Occupants are shrimp and a couple molly babies (till they get too big).

I'm not as interested in crazy growth as in stability, although some crazy-growing till the plants fill out (crypts, micro-sword, java fern) would be nice. I would rather do FEWER water changes as I know I get lazy eventually, and this particular tank is not in a good spot for spills.

If this set-up goes well, I hope to redo the others with the improved substrate (they all have cheap gravel, currently).

Lots of reading on EI, non-CO2 EI alternatives, etc, left me ... greatly informed, but still I think missing a starting point.

What I'd like to work out is...

- What ppm should I be aiming for, if the goal is a non-CO2 tank where water is NOT being changed weekly? (I saw mention of 8-10x less uptake with no CO2, and 3-5x less with daily Excel, but what are the starting points?)

- How much dry fertilizer to mix up in probably 1 liter containers such that I can dose 1 mL per gallon, and get that level? (basically, right # grams to mix up my own liquid "nano fert" bottles?)

- How often to dose? Only when I DO change the water? weekly? every few weeks? every other day, like "normal" EI?

- How to tweak amounts and schedule if I'm adding Excel, and/or doing more-frequent water changes, time/energy-permitting?

(eventually I want to get a big tank going with CO2, EI, plumbing, etc, but that's a few months off).

Thanks, Karl

 

[HepCaribou]

Ok, doing a bit of math based on some figures from the non-CO2 methods article.

Starting with maximum uptake for dense plants, high light, high CO2:

NO3 = 1-4 ppm uptake / 24 hours (average: 2.5ppm)
PO4 = 0.2-0.6 ppm uptake/ 24 hours (average: 0.4ppm)

...reduced by roughly 6x for non-CO2:

NO3 = 0.417 ppm uptake / 24 hours
PO4 = 0.067 ppm uptake / 24 hours

... assuming for non-CO2 tanks I could get away with dosing on a WEEKLY basis, I multiplied these targets x7 days:

NO3 = 2.92 ppm uptake / 7 days
PO4 = 0.467 ppm uptake / 7 days

... I used the Fertilator calculator to figure out how many grams I'd need for a "1000-gallon" tank, as my goal is to come up with a recipe I can mix in a 1-Liter bottle where 1 mL stock treats 1 gallon tank water... I came up with:

NO3 = 18.2 grams KNO3, into 1 liter stock.

PO4 = 2.5 grams KH2PO4, into 1 liter stock.

So....

- How bad is my math?
- How bad is my dosing plan?
- What should I do as far as "K"?
- micronutrients (CSM+B)
- GH? (Houston tap water is pretty hard already...)

 

[Philosophos]

Looks like you've jumped right into things on liquid ferts, and you're actually putting an effort in on the math.

Your math tends to make for some very lean dosing. I dose 1/4-1/2 EI on my low tech tanks. I do everything from the same stock solution whether low or high tech, and simply alter the mg/L that I'm dosing. Keeping dosing well beyond requirements assures that there won't be any nutrient limitations; it's better to start excessive so that you know what your plants are capable of, so you can quickly spot any deterioration as you play with the dosing

K is something that should be at least the same, if not as much as 1/3 higher than NO3. Look to K2SO4 for the rest of your K+.

CSM+B is good on its own; 10g:1L is a common mix that will give you .67ppm Fe in 1L of water for every ml dosed. It doesn't hurt to dose traces like Flourish along side CSM+B to prevent deficiencies in elements that may or may not be covered by your tap.

Now, as for your tap water, get your self a water quality report. If it lacks in information, harass the water department for more details. Odds are that they don't publish every test that they do. Your needs for Mg and Ca are the two main things to cover here. Total nitrogen, phosphorous, iron and copper are good to know as well. After you know what the tap water already provides, you can subtract what it offers from your fertilizing.

-Philosophos

 

[HepCaribou]

Your math tends to make for some very lean dosing. I dose 1/4-1/2 EI on my low tech tanks. I do everything from the same stock solution whether low or high tech, and simply alter the mg/L that I'm dosing.

On your "low-tech" tanks, do you do water changes with those dosing amounts, or just top-offs with the occasional water changes?

K is something that should be at least the same, if not as much as 1/3 higher than NO3. Look to K2SO4 for the rest of your K+.

THAT much higher? I'll definitely need to order some K2SO4 then.

CSM+B is good on its own; 10g:1L is a common mix that will give you .67ppm Fe in 1L of water for every ml dosed. It doesn't hurt to dose traces like Flourish along side CSM+B to prevent deficiencies in elements that may or may not be covered by your tap.

I ran your #'s through the calculator and came up with 0.17ppm Fe. Calculator said I'd need 39grams CSM+B to hit 0.67ppm.

I have an old partial bottle of Flourish here...I thought CSM+B was basically a complete replacement for it? (or does Flourish have more in it than I thought?)

Now, as for your tap water, get your self a water quality report. If it lacks in information, harass the water department for more details. Odds are that they don't publish every test that they do. Your needs for Mg and Ca are the two main things to cover here. Total nitrogen, phosphorous, iron and copper are good to know as well. After you know what the tap water already provides, you can subtract what it offers from your fertilizing.

Nitrate is 0.25-0.50 ppm, Copper is near-nonexistent... the rest isn't on their published report; I'll have to call the city and see what they can provide.

My crypts are melting. Time to fertilize!!

 

[Philosophos]

On your "low-tech" tanks, do you do water changes with those dosing amounts, or just top-offs with the occasional water changes?

On low tech I do 50% water changes every 2-4 weeks, though I've stretched it to 6 weeks now and then. I'm sure you could make an art of it and push things farther with a good system, but personally I don't bother.

THAT much higher? I'll definitely need to order some K2SO4 then.

You can try it without, but IME it's just an invitation for little pinholes all over your plants from K+ deficiency.

I ran your #'s through the calculator and came up with 0.17ppm Fe. Calculator said I'd need 39grams CSM+B to hit 0.67ppm

It should've been 6.53 actually; I had the concentration memorized wrong. The math on that calculator is still way off, though. CSM+B is 6.53% Fe EDTA, from there:

10g CSM+B = 653mg Fe
653mg/1000ml = .653mg/ml

I have an old partial bottle of Flourish here...I thought CSM+B was basically a complete replacement for it? (or does Flourish have more in it than I thought?)

Flourish has a greater variety of nutrients in lower quantities. I use it to round out CSM+B with the occasional dosing. You may find this link useful:
Fertilizer Comparison Chart, by Giancarlo Podio

Nitrate is 0.25-0.50 ppm, Copper is near-nonexistent... the rest isn't on their published report; I'll have to call the city and see what they can provide.

If you can't get the information, just KH test your tap water. If your tap shows up with a couple degrees KH or more, just dose for 5-10ppm Mg and the same in Ca.

-Philosophos