Help diagnosing a plant issue...picture included

It may be a potassium or Nitrate dficency, I had the same problem once. It may also be a light issue as I also had an aponogentum which was in shade and it didn't do to well. Try moving it if you can, c what happens.
 
Calcium and Magnisium are the main contributing things that make water hard, so I would guess it isn't a problem for you. I have a pretty soft water source and have to add just a little to keep things healthy. It doesn't take much, but if your plants are growing well and you have soft water there is the potential to run low.

Epsom salts provides magnisium and I haven't found a local source of calcium so I'll have to order from http://www.gregwatson.com/ . He is a hobbiest that buys the compounds used to dose nutrients in bulk so he can offer small ammounts for pretty cheap.
 
Emg said:
Well, my water is pretty soft...about 80ppm last time I checked....the ph runs about 7.8-8.0. I add about 1/2 teasp of aquarium salt per gallon to the water...but I imagine that is quite different than epsom salt.

Aquarium salt will get you NaCl but what you need is calcium. Calcium can be derived from CaCl (reefers use this, there are many brands out there) or you could put a little crushed coral in the gravel. Go slow, you might only need a small handful of coral. If you are dosing CO2 (which you arent) it coral is a great buffer against the pH drop that happens when something goes wrong.
 
CorydorasLover said:
At most 'aquatic plant' sites, they really recommend 2-4 watts/gallon for a planted tank and it looks like you have quite a few plants in there.


Lol...yeah, it looks that way from the picture....but actually that's only two plants...two different types of aponogeton.....I took the pic up close and personal so it looks very busy in there. I have those two plants plus some tall type of amazon sword I believe.....some water sprite and a few small anubia.
 
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