[newday3000]

I want to understand the EI dosing solution better. Need help to understanding 1 thing.

I have read many dosing solutions and target PPM recommendations of each Macro/Micro for a given tank volume.

I wanted to know if the goal is to dose the target PPM for the whole tank volume 3 times a week (which means you're overdosing by a factor of 3 assuming plants will use up a % of the Macro and Micro during the week then reset the Nutrients with a water change.

OR

Should the Dose done 3 x weekly be 1/3 of the tank volume target PPM? This assumes at the end of the week the tank target PPM is reached but not exceeded and for a couple of days the tank has exactly what it needs for the volume of water and the Water change will reset to a very low level and dosing starts again to build up the PPM but not exceed the tank target.

After much reading on many forums, I could not answer the above question.

Can someone help me understand this better.

 

[dewalltheway]

I am no expert but I have been doing the EI method for about 2 years. First off...EI stands for Estimative Index and that is what EI is "Estimated". Each tank has a target level but each tank can be so different as well. Take lighting. Some tanks are high light and some tanks are low light. The plants in these 2 tanks are going to take in nutrients and CO2 different because of the amount of light. You also have some tanks that are heavily planted and some tanks that are not. This will also effect the uptake of nutrients in the water column.

So...with all that said, the EI Method is used so that there is always an over abundance of nutrients in the water column for the plants to use and at weeks end the 50% WC will lower these levels from not getting to high. The target level is something you can start at, but the plants will let you know if you need more of something (deficiencies) and you may need to increase a certain micro or macro. Some people will say that they are using the EI method but they are getting holes in their leaves, or that their leaves are yellowing. This shows that more potassium or NO3 or iron is needed so you would need to adjust you EI dosing amounts.

This method is used so the hobbiest is not testing their water daily to make sure there is enough NO3 in the water for their plants to grow. You just dose, watch your plants and adjust as needed.