Burning Plants!?

[fastfly48]

That's right. I think I'm burning the plants in my 20g community tank!

The edges of the leaves on my java fern and other plant (esp. the leaves closer to the top) that looks like a java fern (forgot name...doh! sorry...) are turing black. Like they are being burnt. It doesn't look like just rot either...
I have 2 watts per gallon at the moment and leave my the light on for about 8-10 hours a day. Why is this happening??
Thanks in advance.
Ryland

[travis simonson]

Are the leaves on which you see the black edges older leaves? As they age, the leaves of Java ferns will develop black spots where the sporangia (reproductive organs) are located. This is normal, albeit sort of ugly. If this is the case, you may soon see the affected leaves develop small adventitious plantlets along their edges. This is a normal reproductive process for Java fern. Hope this helps

[crazycat]

could it also be algae? i have an anubias hastifolia in my 6g that has a few leaves that are affected this way--black on the edges. every so often the snails cruise by and make tracks in it. the leaf underneath is green and healthy. is this what's called "diatomaceous" algae?

[travis simonson]

It could be algae, but the first thing I think when I see a blackened Java fern leaf is that it is just the typically blackening associated with reproduction/age. Especially since fastfly says they look "burned" rather than appearing to have something growing on them. Of course, without seeing a picture, I can't say for sure, I'm just taking guesses

On the other hand Cat, with Anubias I would definitely suspect algae. In my tank the Anubias leaves have a tendency to get green algae on them which turns into a blackish marl over time. My snails will eat this stuff. The black on yours might also be BBA, but it would likely have sort of a fuzzy look to it and it isn't likely that snails would eat it.

[fastfly48]

Thanks a bundle for all of that! Sorry about the late reply!

I just tried wiping/scratching the black off the leaves but, alas, no good.
Only the leaves toward the top look "burnt". It's just around the edges of the leaf, also the edges are curling a little.

I wish I knew the name of the plant that this was happening to. It's leaves look just like java fern, but the leaves grow on a stem planted in the gravel.

i'm afraid my plants are taken a turn for the worst. The java fern and lonely Bacopa Amplexicaulis are fine but the "unknow burnt" plant and Cabomba caroloana (looks like it anyway...) are not so good.
The "burnt' plant is losing leaves and is not looking too good and the suspected caroloana has lost ALOT of greenage and I keep finding it floating on the surface!?
I suspect I was a little heavy handed planting them and did some damage to the stems. I'm adding fert once a week and doing water changes every week.

The ammonia (oppm), nitrite (0ppm), nitrate (about 9ppm) and [acronym:1bef1d43e0="power head or Measure of the concentration of hydrogen ions, depending on context"]ph[/acronym:1bef1d43e0] (about 7.5) are tested weekly. oh and I have 2 watts per gallon, with the light on for about 10hrs a day. Hope that helps!

Thanks heaps for your help.
cheers.
Ry.

[Tiffi]

Is this the plant you call Cabomba caroliniana: http://www.tropica.com/default.asp

Maybe you can look around at www.tropica.com or www.plantgeek.net to find the "unknown" plant. Or you could shoot some pictures? It's difficult to help without really knowing what's going on and which plants are affected.

As I stated in your other post you might want to consider adding [acronym:27d5103499="Carbon dioxide"]CO2[/acronym:27d5103499] with 2wpg and all the fertilizer weekly.

Lighting of 10hours a day is perfect. But I can't really imagine plants burning under water with only 2wpg. In fact I doubt they can burn under water at all. So it's got to be something else.

Like Travis already asked, are the affected leaves new or older ones?

[fastfly48]

Thanks for your help tiffi.
Yes. that's it. I'm afraid though that the it (Cambomba) hasn't/isn't doing well. I've got to get my water plant friend;y fast! Which means adding carbon, iron etc...
Seems i can kill even the toughest plants in my tank!

i'm starting to think that the "burn" must be stuborn black algae.
The affectd leaves are the larger ones at the top of the plant, not the new/young ones at the very top though. The black is starting to look hairy too...

I only thought they were burn't becasue I couldn't scrape the black off and becasue only the big leaves at the top were affected...but it now seems clear it's an algae problem.

I think/know my tank is low on Co2 and other vital nutrients, so the plants are suffering. I'm looking into adding some carbon into the tank somehow!

Seems I've got quite a rocky road ahead of me here!
Thanks for all your help and sorry for being so annoying. I shall do my best not to ask to amny silly questions! wish me luck...
Cheers.
Ryland