Fert dosing advise please

[shift]

I have an 84g medium light tank.
2x t5ho in a Hagen glo fixture the light is about 20-24" above the substrate which I believe is 40-50 par

The filter is a Fx5 with just foam and 2kg of bio rings in the trays running at about 70%

The substrate is an 1-1.5" of mgocpm capped with 140lbs of Eco complete.

Yesterday I stocked up on ferts which is a new experience for me.


If you dose to the flourish specs they recommend 50% weekly water changes. Which seems excessive to me. I do all my water changes using ages dechlorinated water from a 55g drum. I would rather be doing 10-20% weekly water changes. And ideally pre dose the drum water which will do the water changes for my 7 tanks (about 140g total) If I say cut the recommend dose in half and apply to the drum before water changes will this all work out?

[shift]

So this is my current plan (please advise/critique)

I don't plan on doing 50% weekly water changes so i have cut alot of the does down to compensate. (most in half)

Weekly water changes will most likely be 10-20%.



Also i believe my photoperiod is 9 hours per day

[dtejeda.arias]

http://tinycalc.petalphile.com

[owens81jw]

with a tank that large , i think Dry ferts will be better (Cost less)
Liquid ferts will run out quicker than dry ferts

[shift]

Good to know.. When these run out i will probably make the switch.

Do you think my plan of doing 1/2 the recommended doses will work on my tank?(and avoid the 50% EI dosing water changes?)

I have been reading about all the different methods for hours.. its crazy how simple or complicated it can all be..sadly im still in the extremely confused stage.

[Darkblade48]

Originally Posted by shift

Good to know.. When these run out i will probably make the switch.

Do you think my plan of doing 1/2 the recommended doses will work on my tank?(and avoid the 50% EI dosing water changes?)

I have been reading about all the different methods for hours.. its crazy how simple or complicated it can all be..sadly im still in the extremely confused stage.

Theoretically, if you do 1/2 the recommended dosages for EI, you will still need to do water changes every 2 weeks (instead of every week).

EI relies on the fact that you are dosing an excess of nutrients into the water, which will eventually accumulate, necessitating water changes to reset the levels to their baseline values.

If you want to do fewer water changes, you may want to look into the PPS-Pro method of dosing.

[Hoppy]

Seachem's dosage recommendations seem to be for low light tanks, so normally you have to double their recommended dosages, not halve them. I know you are depending on the substrate as the primary source of nitrogen and phosphorous, but it is still a good idea to dose the water with those too.

[shift]

My main reason for half dosing is so i dont need the 50% "re set " water changes.. but maybe I will do a little closer to the recommendations..
Today was my first day of dosing and i did
2ml of Metracide 14
3ml of Floursh complete
3ml of iron.

In 2-3 days Ill do 6mm of potassium

I'm thinking of dosing 2-3ml of metracide 14 daily and the rest of them once a week.