Is my nitrate level considered too low for plants?

[serbusfish]

I tested my nitrate yesterday and it came up around 5mg/l. I was just reading on another site that plants need 10 - 20 nitrate to get enough Nitrogen, with Nitrogen deficiency showing as holes in leaves/yellow leaves.

Now I only have one plant that is currently showing these symptoms, all my others are lush and green. But would supplementing Nitrogen give me more success with some plants? At the moment I dose with JBL Ferropol weekly and JBL Ferropol 24 every day when the lights go on.

I have only been using the Ferropol 24 for a few weeks when the plant in question was already showing holes + losing leaves.

[talldutchie]

5 ppm nitrates isn't too low. Your lush plants as well as mine attest to that. Nitrogen defficiency tends not to show up as holes but rather as a deterioration of the whole leaf. What you're describing may well be phosphate defficiency.

Is it just this one plant?
How long have you had it?
Do you get normal growth on the rest?
How's your algae growth?
Any chance of a picture of the problem?

[serbusfish]

5 ppm nitrates isn't too low. Your lush plants as well as mine attest to that. Nitrogen defficiency tends not to show up as holes but rather as a deterioration of the whole leaf. What you're describing may well be phosphate defficiency.

Is it just this one plant?
How long have you had it?
Do you get normal growth on the rest?
How's your algae growth?
Any chance of a picture of the problem?

Ok, yes just the one plant, ive had it a month or so, when it was smaller it looked fine, but when it got taller the leaves started developing holes then eventually started falling off. Everything else in the tank grows fine, I dont get a lot of algae, I clean the front glass even 2 weeks.

Here is a pic of the plant:

http://i61.photobucket.com/albums/h58/serbusfish/IMAG0421.jpg (http://s61.photobucket.com/user/serbusfish/media/IMAG0421.jpg.html)

[talldutchie]

The fact that it's losing the lower leafs is usually a sign of low light. But yes, this plant is definitely short of something and it might well be nitrogen. I notice you have this next to a lotus, another heavy root feeder.
What's at the bottom of these? Just sand?

[philthy]

I have a similar problem with that same type of plant and I'm trying to solve it with Phosphate and co2. It's a bit early to say the Phosphate was my problem, but I have seen increased growth since adding the co2

[serbusfish]

The fact that it's losing the lower leafs is usually a sign of low light. But yes, this plant is definitely short of something and it might well be nitrogen. I notice you have this next to a lotus, another heavy root feeder.
What's at the bottom of these? Just sand?

I have T5 lighting, yes the lotus grows very well, I havent given it any root tabs but it always grows leaves to the surface which need regular snipping, I think it has actually grown an additional bulb as I felt a hard object under the substrate next to it, now more leaves have sprouted.

Yes I have regular sand only.

[serbusfish]

I have a similar problem with that same type of plant and I'm trying to solve it with Phosphate and co2. It's a bit early to say the Phosphate was my problem, but I have seen increased growth since adding the co2

I use co2 but its only a cheap kit, all it has is a small chamber with a hole at the bottom, to fill it you just spray the co2 can until the chamber fills. Then as it empties spray some more.

[talldutchie]

My theory would be that the lotus steels all the food. Get some root tabs and see what that does. If you have access to a rabbit then also tuck in one or two well dried droppings at least an inch deep.

[Zim]

Sorry to barge in on your post Serbusfish - hope you don't mind. :) btw - is that plant a hygrophila corymbosa by any chance?

Talldutchie - I'm setting up a planted tank and my daughter does have a pet rabbit - should I keep some of his droppings and use it for my tank? I will be using Miracle Gro Organic potting soil capped with gravel for the bottom, so I may not need more nutrients right now, but I'd like to hear more about using rabbit droppings. I use them in the veggie garden right now, but if I can help my tank as well, why not take advantage of free fertilizer? Thanks so much.

Lisa