Dry or not?


Junior Poster
Jun 26, 2007
I just got my first batch of dry ferts today and I will begin doing dosing with the EI method on Saturday July 14th. What are the advantages of adding the dry ferts directly to the tank and what are the advantages of mixing them with tank water before adding them?

Tom Barr

Staff member
Jan 23, 2005
If you use a scale and mix up a liquid batch, you can dose mls more accurately.

But the difference between a tank that has say +/- 2ppm of NO3 over a 5-10ppm range and another that has a error of +/- 0.5ppm is not going to influence a tank.

It potenitally, however, I've yet to see any evidence of it, could be an issue if you dose nano's, as getting th eincrements small enough for teaspoons is tougher for 3 gal vs a 100 gallon tank.

Still, I've kept 8 nano's for the last 3 years without any issues doing it dry.

So............the issue is not real near as I can see.

But some like doing it this way and prefer that over dry powder.
I'd suggest using KNO3 , KH2PO4 and TRaces is seperate bottles and dosing from there. A GH booster bottle is optional if you need GH and a little more K+.

Some add the KH2PO4/KNO3 together.
Really up to you.

Some fine it easier to dose every day vs 3 time a week.
Just take the week's totals, divide by seven instead of three.

Simple enough.

Tom Barr


Guru Class Expert
Feb 3, 2007
Dixon IL
I mix mine in a cup of tank water first. It just helps prevent stupid human errors. I once put KH2PO4 and I thought it was KNO3. I realized it and just disgarded the water in the cup.

Plus if you mix it in water you don't have white particals on your plants and substrate. I dose dry every now and then and there seems to be no diffrence.

I guess it's just personal preference.


Junior Poster
Jun 26, 2007
Right now my planned dosing routine for my 125gal tank looks like this.

1.5 tsp KNO3 3x /week
1/2 tsp KH2PO4 3x /week
1/2 tsp K2SO4 3x /week
1/2 tsp CSM+B 3x /week

The first 3 will be dosed on Saturday (after water change), Monday and Wednesday and the traces on Sunday, Tuesday, and Thursday. This look alright?

I also have a GH booster (Seachem Equalibrium) to add after my WC but is it really necessary?