explaining ei fert adjustments

[rollwave]

Hi everyone,

I'm curious about how others who use EI fertiliser account for the nitrates from fish waste, phosphates in fish food that end up in the waste, and the phosphates in tap water. The EI method seems straightforward without fish, but I'm having trouble figuring it out with them in the tank.

Thanks!

[Surly]

The concept behind EI is that adjustments aren't necessary. The accuracy of testing methods is questionable, and nutrient levels can fluctuate significantly. Even your water supply's chemistry varies with the seasons and rainfall.

EI proponents argue that having too much of a particular nutrient isn't a concern, as long as all essential nutrients are present. The focus is on preventing deficiencies rather than maintaining specific chemical concentrations. This approach assumes a high-tech tank with substantial CO2 supplementation.

[bailite]

What Daize said, and as a general rule, if you're not running CO2, you can get away with about a third of the EI dosage.

[rollwave]

I've got pressurized CO2, which now makes sense of the EI article's explanation that a lack of certain nutrients can lead to algae. Initially, I was concerned that adding mag, phos, plus the phos in tap water, would essentially be laying out a feast for algae.

Been running this setup for a week now, so it'll be interesting to see how my tank progresses, especially when compared to when I was using an off-the-shelf all-in-one fert. Thanks for the insight, guys!

[bailite]

If you want to tweak things down the line, there's an Easy E.I. Calc you can use.