My stock solution


Junior Poster
Feb 17, 2005
Hi All,

I was hoping to get a little advice or some suggestions regarding the stock solution I mixed this afternoon. This will be my first foray into dosing, which i will be commencing once I have time to harrass a few bits of algae I have.

I have a 21 gallon aquarium, light fish load. Lighting is 36W PC and 18W Juwel T8.

Pressurised CO2 currently out of use (as is the 36W light, in order to slow algae growth pre-dosing).

Also, substrate layer of Sera Floredepot as advised by local shop.

So, having removed algae, I intend to restart lighting and CO2 and commence dosing. What do folks think to my stock soln. composition, and dosing as follows:

In 167ml H20
1 teaspoon KNO3
1 teaspoon MgSO4+7H20
2 teaspoon K2SO4
2 teaspoon Chelated Trace Mix (from Chempak, UK) - comprised of: Fe 3.35%, Cu 1.7%, Mn 1.7%, Bo* 0.88%, Zn 0.88%, Mo* 0.023%.

*= not chelated.

I am proposing to dose 10ml daily of this solution, based on the use of Chuck 's calculator with KNO3 as proxy. Am I right????

Ian H

Guru Class Expert
Jan 24, 2005
Shipley, West Yorkshire, UK
Re: My stock solution

Initially I think your dosage is too high. I used a similar quantity of chemicals diluted in 250ml and dose at 5ml per day. I have a 20 gallon tank with 2x36w pc + 18w T8 lighting with pressure CO2 and heavy,rampant planting.

I use the Chempak traces but a different formulation of Fe 3.3%, Cu 0.25%, Mn 3.0%, Bo 0.1%, Zn 1.0%, Mo 0.005%, MgO 7.0%. I prefer the look of this mix as I was a little concerned about the copper levels in yours and mine has additional magnesium.

I do a 25/30% weekly water change. Recently I have started to dose the traces separately on alternate days.

To conclude, as you have a lower light level than myself and particularily if you haven't got heavy planting I would dose at most 5ml, keep an eye on your plants and fish and adjust if required.