Best thing to do is the following: (Note I just made all my solutions last night based on the 40-60g dosing)
Figure your dose size say 15 or 30mL
At 15mL you get ~33 doses or 11 weeks of dosing.
The numbers below are for 40-60g dosing for my tank, I will dose at 15mL but if you doubled the dose to 30mL you could use the same measurents, shake bottle well prior to dosing as some of it will seperate.
KNO3 was 16.5 tsp to 500mL of water
KH2PO4 was 4.125 tsp to 500mL of water
K2SO4 was 4.125 tsp to 500 mL of water
Super Trace Mix was 4 tsp CSM+B, 1 tsp Ferrous Gluconate, 1 tsp Iron Chleate 13%, 1 cap full Flourish Excel (helps prevent mold in the mix) to 500 mL of water. This is dosed at 10mL for a 40-60g tank
You could easily use my measurements but dose at 30mL and get 5.5 weeks of dosing for you 90g tank. For the trace mix you would just dose 20mL.
Couple notes 3 tsp= 1 tbls, a small funnel will make getting the dry ferts into the bottle easier, lastly I use RO water for my mixes
Hope this helps.
Fluval Spec III Shelf!
"C'mon, they're just plants, man, no big deal -- try some"
Last edited by Craigthor; 03-02-2010 at 12:11 PM.