29G Mineralized Tank Water Parameters

[jcali10]

I tested for ammonia, nitrates, nitrites and pH today, and got readings of 0, 0, 0, and 6.4.
I tested the water because I wanted to make sure it was okay to add the 5 sterbai corys
I bought today. I was surprised it tested the way it did. I guess I'm wondering if I should
skip my weekly 50% pwc tomorrow.

[chris_todd]

Those readings sound good to me, though I'm surprised the pH is so low, if you have the same Catonsville pH 7.6-7.8 water I have. Plus, I have about 10 ppm nitrates in my tap water. So if your tap water is like mine, then my guess is your plants are sucking up all the nitrogen you have.

Are you doing CO2 on this tank? What's the KH?

[jcali10]

I am running pressurized CO2, and kH is reading 5 degrees or about 90 ppm. I dont know how long pH test kits last, I've had mine for 3 years, with plenty left because I seldom use it. My pH has always measured about 6.5. The last 2 times I measured pH in my 50G was in Nov 08, and Dec 08, and it measused 6.5 also and that tank has SMS substrate and pressurized CO2.

[Aaron]

Running CO2 will lower the pH by about a point so that's likely the difference.

Also, SMS softens the water considerably and will also attribute to a lower pH.

In both cases it's a good thing. Keeping the pH below 7.0 helps to ensure that ammonium has less chance to convert to ammonia.

[jcali10]

I guess I should be satisfied with the readings in my 29G. When I'm dosing the water column, as in my 50G, I expect to find nutrients in the water. I guess it is normal for my 29G to be devoid of nutrients since I am not dosing any ferts at all. The plants must be sucking up any nutrients given off by the 6 false black tetras and now 5 sterbai corys.

[Aaron]

Yes, you won't read much in the way of macro nutrients in the water column with a mineralized soil setup. Don't worry though, the plants will get what they need in time.