I'm thinking that this is from a lack of iron? I've recently started adding iron chelate to my fert regiment to bring the levels to .4 ppm a day to try and solve it. Wondering if anyone can confirm that this is indeed from low iron.
Maybe it is potassium then... I've switched to PPS-Pro about 2 weeks ago and the plants are getting ferts on a more regular basis now as well. I think I'll wait a couple of weeks and see if there are any changes. I was using the EI method before, but I was not as consistent as I should have been with it.
Ok. One more question (for now). I've pulled this plant apart and done some cleanup in and around it. I'm also wondering if it could be suffering from excess phosphates. The tank water itself is not... but there was quite a bit of dead matter at the base of the rhizomes of this plant.
I read somewhere that high phosphates can lead to black and brown leaves that then die. High debris can lead to high phosphates. Thanks for the link! I've done quite a bit of chasing through the web looking at pictures and haven't seen this exactly. I am leaning on what advice I've been given and acting accordingly. I'm just trying to explore all avenues in case the problem turns out to be something else.
Not knowing exactly what this is, I've taken steps to ensure that the nutrients added are at optimal levels and I've tried to make sure that there isn't excessive amounts of debris around the base of this plant. Before switching to the PPS - pro method I was fertilizing with the EI method. I switched due to not always being able to do 50% water changes. Sometimes I do 25% water changes 2 times a week instead... which still doesn't add up to a full 50% change meaning it was hard to 'reset' the fert. amounts in the tank. All other plants currently look good... just with the exception of the java, which will probably turn around in a matter of time. All parameters should be ideal now.
I also have the same problems with java fern. But i am dosing potassium daily,increasing it by 5-6 ppm. Water changes are done with RO water adding potassium to 30 ppm. Iron is 0.5 ppm. But despite heavy potasium dosing ,leaves of polysperma show its deficiency...Other plants ,even so called difficult to grow , like eriocaulon setaceum,macranda,blyxa ,myriophylum tuberculatum are growing without problems. I noticed some improvement in java fern growth ,when i switched from KNO3 dosing for nitrates to seachem nitrogen. My idea is ...maybe my fern is unable to use nitrates due to high potassium level? I cant measure my potassium,but i would nor be surprised if it would be 60 or more ppm now.
i just got my water results from laboratory and here they are:
According to fertillator ,recomended magnesium levels are 2 - 5 ppm. So it seems like i should remove Mg when reconstituting RO water. But on the other side Mg:ca ratio is 1:3 and it is ok. Gh is 6- 7 ant that is fine too. Dont know what else is wrong???
Those are tank levels? Its safe to assume that however you're adding Ca, Mg, and Fe includes a "comprehensive" trace, yeah? If so, I think you should reset your troubleshooting and start over on the more obvious signs: CO2 (C is your biggest nutrient by far) and are the big leaves of a too tight bunching of H. Polysperma causing too much shade on old growth, and if its the latter but the tops look good and are sustainable, should you replant or just hide it with hardscape or a mid height grower .
yes,these are my tank levels. Co2 should be fine ,because it is controlled by Ph computer and it is set to 6,5 - 6,4. my KH is 4-5, i know according to PH/kh co2 chart this should be too much ,but fishes are fine.
You are right about shading. polysperma is shaded,sometimes very seriously.But java fern is not a plant,that needs lots of light. But generally i agree that shading is one of the reasons that its leaves are turning black.
Looking back at old threads! Thanks Newt for that link, I've used it since then more than once. This tank was rebuilt in January of 09, since then there are no more problems with the Java fern. I now add magnesium and calcium to the tank on a regular basis and I think the problem with this java was a lack of magnesium for what it's worth. The water I use out here is very soft, almost no minerals in it. (It's snow melt). Thanks for the input from everyone!