[Zapins]

Replied on APC: http://www.aquaticplantcentral.com/.../90585-whats-wrong-my-nymphaea-lotus-red.html

Likely potassium deficiency, in Nymphaea species the holes are not small pinholes like in other species but rather huge lesions that appear very quickly, sometimes within a few hours, enlarge and can kill entire leaves. Also happens in Barclaya.

 

[Zapins]

I disagree as some "melting" leaves in Nymphaea are rather common: 1-2 melting leaves surrounded by 20+ perfectly healthy ones. The ones that melt are either the oldest leaves on the plant or the youngest.

You can also achieve the same result by:

• slightly "folding" the stem
• trimming the roots
• too long exposure to air
• temperature change up or down
• replanting

These are certainly possibilities in general for damaged lotus plants, but in this specific case the older leaves are damaged with no new leaf involvement at all. This pattern usually signifies a mobile nutrient deficiency.

Since his plant has been in the same spot for 2 months these are unlikely to have occurred.

• trimming the roots
• too long exposure to air
• temperature change up or down
• replanting

This is a possibility, but even severed leaves left in water will not decay like this for days even weeks at a time, furthermore why only the oldest ones?

• slightly "folding" the stem

All this points towards a nutrient problem, probably potassium.

Read through my new DeficiencyFinder entry for potassium deficiency in another Nymphaea species:
http://deficiencyfinder.com/?page_id=789

 

[Zapins]

I don't know, I have had a few and many have done this, just to grow back perfectly. I don't want to say you are wrong, and you are my plant mentor, but I have never not had this plant suffer unless, something else is suffering.

Not sure if you meant this post for me or for OVT, if it was for me, I don't mind. I'm not always correct about every problem. I like to work my way through the list of likely problems then move on to less likely problems.

The OP posted a picture of his A. reineckii on APC which also has holes. The OP didn't post that photo here so I suppose I have an unfair advantage coming to this thread.

Most of the holes look a lot like nerite holes since they are fairly irregular and seem to lack the boarder that potassium deficiency has. However, not all the holes look like nerite damage and nerites will often eat weakened plants, or eat dying patches of plant tissue. So perhaps the nerite simply ate through the leaf where the potassium deficiency symptoms are. Either way two plants in the tank with potassium-like holes seems to suggest a possible lack of potassium, which is easy to test and rule out.

 

[Zapins]

Any news on the problem?