onion plant (Crinum thaianum) Trouble

[bigbruce]

My onion plants have started getting brown gouges down their sides like uneven bite marks, these seem to eat into the leaf until the upper bit breaks off.
Only a few per strand.
Also the colour seems to be fading at the sides dark green in the middle and yellowing to the edge.
The other plants are fairly healthy i have co2 and fertilize daily
Its not snails and the goldfish leave it alone the only ones that go near are the sucking loach.
Anybody have any ideas

 

[hellohefalump]

this happened to me on my Crinum Callamistratum. Although the patches were more red than brown. It was like they were rotting?

Someone told me that C.Callamistratum didn't like to be moved (my plants were fairly new at the time). I'm pleased to say, I left them well alone, put some root tabs under them, and the problem gradually cleared up and they're now very big, healthy plants.

I've never had an onion plant, but they're from the same family so I'd imagine this is a similar problem to what I had?

Is your C.thaianum new to the tank?

 

[Ed Seeley]

I had 6 in my tank and lost one that was moved from another tank after a few months and now one of the new ones has recently floated up from the substrate. It seems its roots rotted off and a lot of leaves are too. They started with dark patches too. It seems to be recovering now but I'm not too hopeful! The strange thing is the others are thriving and multiplying.

 

[bigbruce]

The plants (2) have been in for about 11 months and seem healthy apart from the leaves.
The roots look healthy with lots of little rootlets breaking through the gravel.
I have put down some root tabs nearby maybe i'll stick another down
The only thing i can think of is that it's the area where i put my ferts in, would excel flourish do anything on contact?