# Nitrate Level w/ EI Dosing



## southernflounder (Nov 5, 2006)

What is the nitrate level that I should be aiming for w/ EI dosing? 

My Nitrate was originally 5 ppm now it's 20 ppm, should I go higher? My concern for higher nitrate level is how it will affect the RCS in my tank. On that note what's the upper limit of nitrate for keeping red cherries?


----------



## hoppycalif (Apr 7, 2005)

If you are going to use the EI fertilizing scheme, don't try to finesse it by measuring nitrates or phosphates. Just dose per the table. You won't build up enough nitrates or phosphates to do any harm if you do that. The whole point of the EI fertilizing scheme is not to measure, but to estimate, then to do big water changes every week to reset the tank fert levels back down if they have been creeping up due to the dosing.


----------



## southernflounder (Nov 5, 2006)

Thanks for the reply Hoppy. Let me re ask the question then:

When using EI dosing what will be the highest nitrate level obtained?


----------



## Laith (Sep 4, 2004)

When using EI dosing and 50% weekly water changes, the highest level of NO3 (or anything else you dose) will never exceed twice your weekly dosing. So if for example you dose 7mg/l of NO3 three times a week (21mg/l a week), your NO3 level will never exceed 42mg/l.

In a well planted, well lit CO2 tank, it will never reach that high as that figure doesn't take into account any plant uptake, of which there should be quite a bit (otherwise something is wrong!).

Of course the above assumes one is not overstocking their tank with fish.  

20mg/l is fine. No need to raise it.


----------



## detlef (Dec 24, 2004)

On a little side note here which might not be so unimportant as we're all forgetful:

NO3 through EI adds N on top of what already went into the tank by the tap's NO3. If you use EI, have a good fish load and say 30-40ppm NO3 from your tap then you might run into problems growing plants.

Best regards,
Detlef


----------



## Laith (Sep 4, 2004)

Yes, good point Detlef.


----------



## hoppycalif (Apr 7, 2005)

The nitrates or phosphates in the tap water are the same as a one time dosage of that nutrient. The plants will start using it just as they use what we dose. So, having a certain level of one of the basic ferts in the tap water doesn't eliminate the need to keep dosing it.

Tom Barr has noted that neither fish nor shrimp are affected by nitrate levels up to somewhere in the neighborhood of 100 ppm, and it is shrimp that show the effects first. The plants won't be adversely affected by having an excess of any of the ferts, up to even 5 times what we dose.


----------



## dennis (Mar 1, 2004)

If you have 30-40ppm from the tap, complain to someone as that is unhealthy. Here in the states (not that we are necessarily right) NO3 in tap>10ppm is considered unhealthy, especially for children, infants, pregnant women, etc. It can lead to "blue baby syndrome" (hypoxia I think is the correct name). Anyway, if you have that much in your tap you may have more to worry about than your cherry shrimp.

The math, as Laith point out is pretty fool proof, but it requires a 50% or more wc weekly. A slowing of growth for some reason or an increase of organic N sources (major rescape or substrate disturbance for example) can lead a higher NO3 level very quickly. I have seen a 20ppm+ jump in 3 days after a major rescape or substrate disturbance. Bottom line, EI works great but it is not 100% fool proof. You need to occasionally think ahead about you situation and stay on top of water changes.

In regards to fish and shrimp health, I have noticed a major increase in baby cherry shrimp and almost no adult deaths since dropping NO3 levels below 50-60ppm. My fish also display better color and not as many go carpet surfing. I don't put any faith in one person's (Tom's) statement that high nitrates are not harmful to fish and shrimp. I and many other much more experienced aquarists would argue otherwise.


----------

