This is another of the open ended answers with no actaul yes/no. lol
Crypts can suffer crypt melt when moved within the same tank. Why. Noone knows. Does it happen to every crypt. No some people say they regularly move their crypts with no problems even from tank to tank.
So we can say that Crypts don't always melt when moved wether it is within the same tank or to another tank.
My theory is that Crypts are highly susceptible (as is Blyxia) to changes in their environment. My guess is that when you buy a crypt it normally (but not always) melts when you plant it in your tank. I beleive that this is because your tank water, substrate, lighting etc is different to what they had prior.
When you move a Crypt from one place in a tank to another place in the tank you may say the substrate is the same, the water is the same and the light is the same. Nope you are wrong. Substrates are very different in different places. Some fish may like a particular spot and therefore they will disturb that spot or poop in that spot etc. Also the plant may have been next to a stem plant and is now next to a plant with a large root structure like Echinodorous. Therefore this may be a change in the nutrient or even oxygen available in the substrate.
Even with high turnover of your filter there can be 'dead' spots in the water where the nutrients are not as good as other positions. There will be many differing qualities in the circulation within your tank and the circulation will transport nutrient at differering quantities to different places. This is the continous fight we try to sort out. How to ensure that nutrient (including CO2) delivery is as consistent as possible.
With the light the amount will be incredible different positions. The light is small. the footprint is much larger. the water can be a barrier, other plants can be a barrier. diagonally the light has to travel further etc. for example if you have only 1 crypt in your tank and it is directly under the centre of your tube. It receives the max light it can get through the smallest amount of water. Move it to the front or rear corner. No it is not under the tube and the light is coming through a larger amount of water. This is why all tanks are darker in the corners. This is not as noticeable in higher light planted tanks but it is still true.
So in summary I think it is changes in parameters that affect Crypts. I think theses changes are unknown and some people are lucky enough in that there isn't a significant enough change when they do move their crypts. Do I think they like company.lol. No I think they prefer to be planted as you bought them in a clump without spereating them or you are making a change!!! I seperate them because I want the effect that gives. So mine rot yes.
Can I prove any of this? No it is all pure speculation from my experiences and reading others. Not factual at all, only theory. What are the facts? The fact is if your crypt does rot don't worry remove all the rotting leaves as you see them and then let it regrow.
Andy
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