[32Bit_Fish]

Hi All,

I have a heavily planted 75G with some small tetras. The tank has been up and running for 2 months now. Water is being filtered by a SunSun 303b four stage canister. I do 50% w/c weekly.

I tested water for nitrate yesterday and surprised to see 7 ppm of nitrate reading. I thought it should read 0 nitrate in a such heavily planted tank.
I have 39w T5HO on 8 hours a day and pressurized CO2 7 hours a day. PH has also been kept steady at 6.9. My tap has 6.8 PH.

Does this mean the plants are growing slowly with low light and low level of CO2 injection? I had the PH reading of 6.2 before when I was pumping CO2 into the water and with 78w T5 HO on 10 hours a day.

Now I turned everything down, so plants use less nitrate. Hence I can detect nitrate in the tank?

 

[jrill]

I don't think you will ever see 0 unless you do a large water change. My low light 20 gal long stays around 5.

 

[32Bit_Fish]

I don't think you will ever see 0 unless you do a large water change. My low light 20 gal long stays around 5.

The nitrate reading was a day after a 50% w/c. I would expect all nitrates supposed to get used up by plants. Its odd.

 

[jrill]

I don't think you will ever see them all get used up unless your tank produces very little ammonia like with a very small bio load. Do u have a lot of fish and feed them heavy?

Sent from my DROID RAZR HD using Tapatalk

 

[32Bit_Fish]

I don't think you will ever see them all get used up unless your tank produces very little ammonia like with a very small bio load. Do u have a lot of fish and feed them heavy?

Sent from my DROID RAZR HD using Tapatalk

Here is my fish stocking:
- 9 lemon tetras
- 2 red rummy noses
- 12 cardinals
- 1 small boesemani rainbow

I'm going to add 6-7 adult discus in this tank over the course of a few months. I guess I will see nitrate level will rocketing if massive w/c are not done.

 

[gSTiTcH]

7ppm is nothing to worry about. You don't want to see 0 ppm. With 0 comes unhappy plants.

 

[Italionstallion888]

I would be a happy man with nitrate numbers that low lol

 

[mnemenoi]

We have had Nitrates drop to zero and with that comes all sorts of crazy issues, you definitely want a number there and most EI dosing adds them for the plants especially in a CO2 injected tank

 

[aquatik]

Sometimes tap water contains nitrates already from agricultural runoff. Out of the tap my water is 5ppm nitrates.

 

[Diana]

I think you are right that at the light and CO2 levels you are currently running the plants are not removing all the ammonia/nitrite/nitrate.
Even when you add more fish this may not be a problem, though, as long as you are willing to do water changes.
Or you could go back to higher light and more CO2.

The other way is to grow plants that are above the tank, in the air, with just roots in the tank. There is a lot more CO2 in the air, and if the tank is near a window there is enough light for most house plants.
I have several plants in various tanks and the N readings stay quite low.
Epipremnum, Syngonium and Philodendron have all done well for me in this sort of setting.

 

[32Bit_Fish]

I have high quality tap water here in New York City. PH of 6.8 and free of all other elements such as ammonia, nitrite and nitrate, etc.

So I guess I can make nitrate go away in my tank by going back to the high tech mode (high light, more CO2 and more dosing?)

I have dry fertz at home. But it seems there is no need to use them at this point with low light, low CO2. I dump some liquid fertz in to the tank once a week or longer. Plants are seem to be doing good.

 

[Diana]

Yes, when I was running a lot of tanks and changing lighting and CO2 levels that is when I noticed changing requirements for fertilizer.

Low tech: Plants did not remove enough NO3 (Tanks were heavily stocked). Plants showed deficiencies of potassium and iron.

Medium tech: (higher light than before, added Excel): Plants were a lot better at removing NO3, but there was still some. However it varied a bit, so I got into the EI method, dosing everything and doing big water changes.
I have gradually scaled back the dosing to suit what the plants seem to need.