Seachem dosage amount?

**Ingen** · 20th May 2013, 17:14

Hi Guys,

New to planted tank (wall mount 27L tank) and been reading on fertilizer dosage. I realized there are two conflicting dosage that are being suggested online.

1. A Seachem excel chart that detail the amount based on the size of the tank. It suggest 0.6ml flourish Phosphorous 2-3 x a week. (http://www.aquaticplantcentral.com/f...tor-chart.html)

2. A EI Method calculator based on the size of the tank and products. It suggest 12ml 2-3x a week. (http://calc.petalphile.com/)

The difference between these two are too huge for comfort.

Would appreciate if someone that been using Seachem products would provide some insights to the amount I should be dosing. Currently, I am dosing Flourish comprehensive, Flourish Nitrogen, Flourish Phosphorous based on (http://calc.petalphile.com/) I fear it's way too much...

**Urban Aquaria** · 21st May 2013, 01:58

Both charts calculate dosages based on different fertilization concepts.

The Seachem dosage chart is based on small dosages everyday and very minimal 5% water change at the end of the week. Since the water change is so small, excess nutrients will accumulate in the water, hence the smaller controlled dosages to prevent excess nutrients.

The main issue i see with the seachem dosage chart is that it doesn't factor in the plant density in the tank... consider this, it can't be the same dosage for a tank with 2 lonely slow-growing anubias plants, versus a tank stuffed full of fast growing stem plants right?

At best, its just a very rough guide so you'll have to further adjust the exact dosage through closely monitoring the plant growth and demands.

On the other hand, the estimative index (EI) method is meant to over-saturate the tank with nutrients. The concept is based on the approach that we don't know exactly how much nutrients the plants want, so its better to overdose nutrients (rather than under-dose), and then at the end of the week, a large 50% water change is done to remove the excess nutrients and reset the nutrient levels before overdosing nutrients again, hence the much larger dosage amounts.

Hope that helps!

**Ingen** · 21st May 2013, 09:19

Thanks for the info!

As the dosage can be as much as 10 times or higher for EI method, would it have adverse effect on livestocks? I have cherry shrimps, a pelco and 4-5 indostomus paradoxus?

**Urban Aquaria** · 21st May 2013, 13:57

Originally Posted by Ingen

Thanks for the info!

As the dosage can be as much as 10 times or higher for EI method, would it have adverse effect on livestocks? I have cherry shrimps, a pelco and 4-5 indostomus paradoxus?

Yeah, that's the unknown factor... but it seems to be relatively safe as i've not heard or read of any reports about excess fertilizers affecting fishes or shrimps so far, seems the only issue is the water TDS rises, but then that is also somewhat regulated by the large 50% weekly water change anyways.

The only thing negative about the EI method is that it uses up alot of fertilizer (alot of wastage that ends up getting thrown out during the weekly water change, best to use it to water house plants instead, don't waste all the excess ferts

), so it'll end up increasing costs if using pre-mixed branded fertilizers.

Most people who do the EI method usually use dry ferts instead, which are much cheaper.

**Ingen** · 21st May 2013, 14:10

I see, any place to recommend where all the dry fertilizers are readily available?

**Urban Aquaria** · 21st May 2013, 14:30

Originally Posted by Ingen

I see, any place to recommend where all the dry fertilizers are readily available?

You can try this website: http://www.ecocityhydroponics.com/

**Ingen** · 21st May 2013, 15:36

THanks!

Is this what I should get for N,P,K http://www.ecocityhydroponics.com/lu...-ka-1-kg.html? For micro, can I just use Flourish Comprehensive, as I realized the micro nutrient from ecocity contains copper, which is harmful to shrimps?

**Urban Aquaria** · 21st May 2013, 20:23

Originally Posted by Ingen

THanks!

Is this what I should get for N,P,K http://www.ecocityhydroponics.com/lu...-ka-1-kg.html? For micro, can I just use Flourish Comprehensive, as I realized the micro nutrient from ecocity contains copper, which is harmful to shrimps?

I've not used that particular formulation before so not sure about it... maybe the plant experts here can chime in on it.

Most people would go for these:

CaNO3 = http://www.ecocityhydroponics.com/lu...m-nitrate.html (as a substitute for KNO3)
KH2PO4 = http://www.ecocityhydroponics.com/po...phosphate.html

Seachem Comprehensive should be able to cover most of the micro nutrients, can also try Seachem Trace too.

Not sure about the micro nutrients from the site though, so i guess its better to use the Seachem products to be safe.

**Ingen** · 12th Oct 2013, 00:50

Old thread. Went to restock my seachem fertilizers and it brought about a question that I had forgotten. Any idea what's the main difference between Comprehensive and Trace? I used to dose comprehensive, but I bought trace today hahah.

Another weird situations, I tested both my 2ft and wall mount tanks and it has 0 nitrate readings. I reckon I should increase seachem nitrogen dosage?