No new plant growth

[jayhitek]

Hello,

I have Never been able to get any new plant growth of any kind in this one tank. Right now all that is in there is anubias and crypts. You can see some pictures of what the plants look like and I am wondering if they are showing any clues as to what is missing..

The plants don't melt.. they kind of just shrink and disappear.

The tank has been running for about 9 months.
It's a 300 gallons (probably about 250 gallons of water).
I dose with Potassium (60ml) and Flourish (Comprehensive 20mL) 2x per week. And Iron (30mL) 3x per week.

I have a CO2 system in place that is only on when the lights are on. About 4 bubbles per second. The last time I tested the KH it was about 35 ppm.

The substrate is CaribSea Eco-Complete Planted and in the past I added Seachems Iron tabs and PondTabbs.

To me it's almost as if all the nutrients are getting sucked up by the water and the plants aren't getting any.
Any ideas at all of what else I can try? Or something totally different from what I am doing now.

One more thing I changed last month. I originally had automatic water changes going off every night and changed 6 gallons per night but then I thought that the nutrients were getting used up by the new water. Last month I shut the auto changer off but no improvements.. Same plant situation.

Thank you,
Jay

[Tech Support LK]

Sometimes nitrogen can be a limiting factor and cause stunted plant growth along with other issues. Do you monitor nitrogen levels at all or dose any nitrogen supplements?

[jayhitek]

I do not think I have ever tested the nitrogen levels..
I actually have never seen a Nitrogen test kit.

Are you recommending that I try the Flourish nitrogen product?

The instructions are a little confusing for the first couple of doses. How much should I dose for 250 gallons of water and how many times per week?

Thank you for the help,
Jay

[Tech Support LK]

Before adding additional supplementation, I would certainly recommend purchasing a nitrogen test kit. We do make a test kit that measures nitrite and nitrate. A simple calculation will give you a value for total nitrogen (the calculation is on the instruction sheet for the test kit). Here is a link to this product if you are interested:

http://www.seachem.com/Products/product_pages/MT_Nitrate.html

As far as dosing, that would depend upon what your current level is at. If you want to measure total nitrogen based on nitrate levels, then you would use the formula given on the instructions. First, I would find out if nitrogen is actually limited in your tank. We can figure out the correct dosing for you once that has been verified.

[jayhitek]

Ok thanks.

I will test the nitrate and nitrite to find the nitrogen level.

[Tech Support LK]

You are very welcome.

[jayhitek]

Tested the water:

The Nitrite is less than zero.. No color at all.
The Nitrate is between 5 and 10.. Probably around a 7.

So now how do I calculate the Nitrogen level?

[Tech Support DD]

To convert your nitrate level to nitrogen, you can divide by 4.4. Since your nitrate level is in the 5-10ppm range, you are actually at a good level. However, some people suggest that the nitrate level in a planted tank should be around 20ppm, so you could try raising this level some, if you wish.

[jayhitek]

How much do you recommend that I dose of Flourish Nitrogen and how often?

Should I just follow the general instructions on the bottle? Since I am working with 250 gallons of water the dosing allaws appears extreme to me..

[Tech Support DD]

A good starting point is to follow the general ("Beginner") instructions on the bottle. For your tank, that would be about 3 caps once or twice a week.