Yes you can! that is how I started. I got g-m-b and superthrive.

then I discovered liquid karma...Great stuff...covers alot of beneficial elements and acids.

Then I started into enzymes, but you can use h202 if you are pure 3-part. and you can add a little epsom salt for magnesium.
Enzymes are important for root health.

I eventually tried most of advanced nutrients and still use a few...
Bud Blood ...big bud...And Overdrive, all get used in succession and never together, so They last awhile. I still have 1/2 bottle of final phase, but have been using florakleen..both good.

But; In answer to your question; You would actually be wise; To use just the 3-part, because it is so simple to get good healthy growth and you will then, truly be able to measure the advantage of any additive you decide to try down the road.

here is a pretty much foolproof recipe:
seedlings...NO nutes. Once they have grown to 4-5 nodes(alternating leaf sets) then you give them 5 ml of each part per gallon...that will bring you to an ec of around 800 to 1000 depending on your water. (if you use distilled or RO water...then you must add calcium and magnesium back into the solution, because these elements are essential) MY Well water will has just about 167ppm. City water varies greatly. so it is important to know what is in your water.

once they take off you can give them 8ml each per gallon just like the direction's state on the bottle. GH website has a calculator and additive chart if you check it out. Hope this helps you out and answers your Q' I love 3-part and I have grown a Sexy Orange Skunk plant in DWC and yield was 3/4 LB. peace

p.s. 3-part is so versatile, I am sure you can find alot of ways, but this simple method is great for someone starting out.
latewood Reviewed by latewood on . ATTENTION GH's "FloraShield" users..... If you use Florashield by GH as prescribed in their charts like their "phase feeding cart" or "weekly feeding chart", it says to use 37.5 ml. per U.S. gallon of reservoir at every reservoir change. What they don't tell ya' is what the stuff does exactly, and what exactly it contains. THey don't tell ya' that 37.5 ml./gal is NOT for every gallon of every resevoir change, and that it is only intended for specific needs like a root rot problem, or bacterial infection. They make it look Rating: 5