Crypt Tropica Issue - Nutrient Deficiency?

[TresMiller]

have some established Crpyt Tropica that has been having this strange melt issue for a while now. Trying to figure out if its a deficiency. PH 7.5-7.8, GH 75-100 ppm, KH >150 ppm, Fertilizers Easy Green Root Tabs and Easy Green Liquid. You can see in the picture a green spot about 3/4 of the way up the leaf, this spot will progress for 1-3 days across the leaf until it detaches. You can see the progress in the photos this pics were taken within a day of each other. 

 

[Seattle_Aquarist]

Hi @TresMiller

It is not a nutrient deficiency, I am not aware of any nutrient issue that causes what you are seeing however if the ammonia levels are high they can cause more sensitive species to exhibit that condition. Typically I only see that condition when I breakdown a tank and replant my crypts or if I purchase some new cryptocorynes and plant them.  It is commonly called 'crypt melt'.  I can also trigger the same 'melt' if I do a major water change that changes the water parameters substantially.  Do you gravel vac your tank?  Do you check for ammonia spikes in the days following a vac?  Hope this helps! -Roy

[TresMiller]

Thank you Roy, I have seen no Ammonia spikes that I am aware of. I do not gravel vac as I have a medium grain sand substrate. Crazy because these Crypts showed very little melt when converting after planting and have always been "healthy". 

[Seattle_Aquarist]

Hi @TresMiller

If it were me I would double check and do an ammonia test just to be safe.

 

Quote

3. Tissue breakdown – necrosis and firing of the tip and margins of the leaf.
The ammonium cation in itself may become phytotoxic and result in breakdown of the plant tissue (proteolysis -breakdown of plant proteins) initially producing a wet, dark-green, "steamed" appearance at the leaf tips and margins.

 

[TresMiller]

Will do, Thank you again Roy. Definition is spot on "initially producing a wet, dark-green, "steamed" appearance"