what is the correct ppm?

[hirowen]

Hi forumers,

Juz wanted to know whether there is a correct weekly ppm to follow for N, NO3, K, Fe and etc... or is it we have to estimate ourself?
Cuz i m confused after using this spread sheet
Please help...

thanks in advance...

[|squee|]

From the EI by Tom Barr,

CO2 range 25-35ppm
NO3 range 5-30ppm
K+ range 10-30ppm
PO4 range 1.0-3.0 ppm
Fe 0.2-0.5ppm or higher (?)
GH range 3 degrees ~ 50ppm or higher

The above values are a good range to reference from.

[hirowen]

From the EI by Tom Barr,

CO2 range 25-35ppm
NO3 range 5-30ppm
K+ range 10-30ppm
PO4 range 1.0-3.0 ppm
Fe 0.2-0.5ppm or higher (?)
GH range 3 degrees ~ 50ppm or higher

The above values are a good range to reference from.

Yeah...Thankz alot Terrence!

btw..fe can be 0.2~0.5ppm or higher? that means no limit?
and i dun understand GH range 3 degrees ~ 50ppm or higher..
pls enlighten me

[|squee|]

I don't really understand it too. But I believe that Tom is uncertain about what levels of traces will start to cause problems in a planted tank, so he put the question mark there.

For gH, he means 3 degrees or higher (3 degrees approximately = 50ppm)

[hirowen]

I don't really understand it too. But I believe that Tom is uncertain about what levels of traces will start to cause problems in a planted tank, so he put the question mark there.

For gH, he means 3 degrees or higher (3 degrees approximately = 50ppm)

thankz terrence. u solved my curiosity..

[hirowen]

One moe thing terrence...when i dose KNO3...does it means it will increase k as well? Same goes with Kh2PO4? inr in K and PO4?

[Phillipians]

if i am not wrong , K No3 when added also increases K in the tank, but for kh2po4 i m not so sure about it. And Fe dont have to keep too high levels if you are using ADA soil

[juggler]

If you dose KNO3, you are adding K and NO3 in significant amounts. K is 40% and NO3 is 60% of KNO3.

The K in KH2PO4 is insignificant compared to the PO4 you added.

For Fe, I found that 0.2ppm weekly seems enough for my tank. Some folks may like to dose more or less depending on their tank conditions.

Just follow Tom Barr's EI method. And weekly water change.

[hirowen]

Thankz phillipians and koah fong..

[soulfinder78]

For those figures u guys r talking abt does it have a difference if the tank size is different??? or plant types? even lights???

[|squee|]

It makes a difference, the above figures are just guidelines, a reference for fertilising. One tank can have 50ppm of NO3 and is still not enough for plants, while another can have 20ppm of NO3 and enough for plants.

[vinz]

For those figures u guys r talking abt does it have a difference if the tank size is different??? or plant types? even lights???

The numbers are not different for different tank sizes. PPM is Parts Per Million. It is a relaive measurement, not an absolute measurement. A larger tank has more millions, so you have to add more parts, but the final reading is still the same in terms of ppm.

E.g. If 1 teaspoon of KNO3 adds X ppm of NO3 in 100 liters water, then you need 2 teaspoons of KNO3 to raise X ppm of NO3 in 200 litre or water.

But when it comes to plant needs, it can be different. Plants have different growth rates under different conditions and hence require different amount of fertilisers. A tank with more light and CO2 will grow faster and need more fertilisers (higher ppm). A tank with low light and slow plants will need less fertilisers (lower ppm).

The posted recommendations are good general numbers to start with. If you follow the 3WPG recommendation, those number will serve well mostly. In Singapore's higher temps, it's not a bad idea to dose more.

The only constant is CO2... 30ppm.

[soulfinder78]

thanks alot that's very informative. but 1 question how will i know how much my plants need??? is it some sort of trial and error basis??? so other than KNO3 what else do u guys dose??? those solution like faster growth for plants brighter colour... are they useful???

[|squee|]

Yes it's on a trial and error basis. That's why people say observe the plants, not your test kits.

What do you mean by solutions for brighter colour? You might want to start a new thread also

For me, other than KNO3, I dose Seachem Equlibrium, KH2PO4 and a commercial trace product. This more or less supplies practically everything plants need.

[soulfinder78]

sorry i'm relatively new to this. where can i get those kno3 all those stuff???
can they be purchase off the rack of LFS???