projectile

best overview i have seen of EI , thanks a lot

ezeke1

Good stuff, thanks for the guide!

Stealth

These ranges, are they weekly totals?

Using the suggestions higher up in the post, in a 50 gal I get
25.27ppm NO3 a week
7.74ppm PO4 a week and
19.11ppm K a week assuming zero plant uptake.

So that puts NO3 & K in the right range, but PO4 nearly 6ppm too high. I realize that Toms point is excesses are ok if there is nothing lacking but this seem excessive when reduced KH2PO4 can be dosed and adding K2SO4 to make up for the loss in K.

I am I reading it right that there is too much PO4 according to the listed target ranges?

John N.

As you noted, the ppms per week represent the chemical accumulation without any plant uptake or consumption. Of course zero uptake is not what happens in our aquariums. The wide ranges listed above describe the daily totals with uptake that can happen through the course of a weekly dosage. What does that mean?

Plants consume a good amount of the nutrients in high light situations each day, however they can't eat all of it! From day one, the nutrient load climbs into the upper excess tiers by the end of the week. The 50% weekly water change flushes the system so that the levels are then reduced.

The more debated day to day range can be denoted as:

CO2 range 25-30 ppm
NO3 range 5-15 ppm
K+ range 10-15 ppm
PO4 range 1.0-2.0 ppm

-John N.

Stealth

Thanks for your reply. I understand what you are saying, but can't understand why all the levels are within the suggested targets except the PO4. As these are assuming zero uptake, is it assumed that the plants will consume PO4 faster than the other levels and so these excessive levels won't be seen?

John N.

PO4 is dosed in low quantities and also consumed in low quantities, whereas the other chemicals have a wider range and wider range of consumption values. It can be stated that 3ppm of PO4 dosed between day 1 and the next dose on day 3 will be consumed to its depletion. I'm not sure if that makes sense to you, but I'm sure there will be a better explanation than mine coming along.

-John N.

mhoy

Thanks for the abundant amount of information. Now to digest it all and figure out what I need to do for my tank.

latchdan

If dosing flourish comp instead of CSM+B how much would i add for a 20-40 gallon tank? Also would i want to add flourish iron on which day? i have a 37 gallon tank

John N.

For both Seachem Flourish and Iron, dose according to the directions on the bottle. Dose both on the micro element dosing days, and do the 50% waterchange at the end of the week as normal.

-John N.

latchdan

ok i will give it a try thanks for the clarification