EI with Seachem Flourish/Trace


Guru Class Expert
Oct 25, 2007
I have just (heavily) planted my 120g (450L) tank. Substrate is Master Soil, CO2 injection and 432 total watts from 8 x 54 watts T5HO tubes. Photoperiod is 6 hours.

I am going with EI method for NPK (KNO3 and KH2PO4), along with Seachem Flourish and Seachem Flourish Trace for the trace.

Q1. Should I start dosing immediately? Or should I start after 8 weeks ? (Ottos to be added after 2 weeks)

Q2. Do I have to add CaSO4 and MgSO4 separately, since they are already present in Flourish?

Q3. Since I will be using both Flourish and Flourish Trace, does this looks good? Or should I be okay by only using Flourish alone?

Sun - 50% wc, NPK ( add CaSO4 and MgSO4 ? )
Mon - Flourish
Tue - NPK
Wed - Flourish Trace
Thu - NPK
Fri - Flourish

Please advise. TIA.
Last edited by a moderator:


Plant Guru Team
Lifetime Member
Jul 6, 2009
The Netherlands
Hi Roger,

You can start to dose immediately, don't wait until deficiencies show up. If your adding Flourish according to the recommended dosage, I wouldn't add anything extra, unless your tap water is very low on these micro's.

What I'm noticing is that you use 432 Watts on a 120 gallon with only 6 hours of photoperiod. I think you have way to much light. You could do with just 3 54 Watt bulb an still grow every plant you want. I'm using 250 Watts on a 180 gallon and a 10 hour photoperiod (more viewing time) That much light will make your tank very difficult to manage, especially considering CO2, it might even be impossible. Algae will take advantage of that.