What is the rationale behind twice the amount of EI Dosing

[faizal]

Hi everyone. Forgive me for constantly having basic doubts on everything but this had been on my mind for sometime now.

Sometimes one is required to dose twice the EI levels of nutrients despite the fact that the planted aquarium being much lower lit than 4-5 WPG.

Now could this be due to the fact that although one did dose EI levels of nutrients from the start,....the emergence of a nutrient related plant deficiency ( e.g. yellowing of new plant leaves,...) could have been atributed to an existing poor flow & hence poor nutrient distribution capacity within that particular tank?

Faizal

 

[ceg4048]

Re: What is the rationale behind twice the amount of EI Dosi

Hi Faizal,
Normally, one should never need to dose any multiple of the EI concentration values, however, it was discovered a few years ago, that large tanks of 75 gallons and over suffer very poor flow and distribution if attention was not paid to this area. Additionally, it was not in the general conciousness to try to achieve to the 10X rule, and which, for large tanks is often impractical.

The inattention to the importance of distribution and flow combined with the propensity for high lighting generated shortfalls in nutrient uptake which were most effectively addressed by increased dosages.

While small to medium tanks are not immune to poor flow/distribution there should almost never be a need to use multiple dosing on these tanks but there may be a need for a small percentage increase. Instead of fiddling with incremental increases though, when troubleshooting a nutrient deficiency, it's a lot easier to simply double the values. So if someone has a GSA problem let's say, and if it's not clear whether this is due to CO2 or PO4 shortfalls, then it's easy and painless to simply double the PO4 value for a quick check. If this doesn't solve the problem then the hobbyist knows the problem then lies in either CO2 injection rate or in flow/distribution, which are much more complicated. So we wind up doing the easier things first when problem solving.

Of course, 15 years ago, people were absolutely mortified at the suggestion of EI dosing levels, and would even have heart palpitations if multiple EI were suggested, but folks seem to be a lot more casual about it now that the so-called dangers have proven to be illusions.

Cheers,

 

[faizal]

Re: What is the rationale behind twice the amount of EI Dosi

So that's why my H. Difformis had yellow new shoots? It was my poor circulation.

Like I have said before,....I don't think I can ever stop thanking you.