Marsilea crenata - dying

[castle]

Unsure what's happening, but leaves are dying off, generally these appear to be older leaves, new ones seem to be fine (for a period). They star by going yellow, and deteriorating to a brown, then nothing. I've read this could be phosphate levels, too high or low..

My growth hasn't been to intense, but they're growing and sending out shoots, so can't complain too much, has been slow compared to other plants tho.

Lights are on for 6 hours a day. I give the tank (60l) a drop of easy carbo every day, and 40% water change each weekend (as of 5 weeks ago).

So, ideas? - also, camera is er, avg.

 

[stu_]

Hi
What substrate are they planted in ?

 

[castle]

Ahh, it's a john innes soil, can't remember the one, but the organic one.

 

[sciencefiction]

Anaerobic soil....
How old is the tank?
It's unlikely to be a deficiency taking into account the rich soil. It's likely that there's lack of oxygen around the tank due to heavy break down of organics.
If the tank is established(several months old at least) then it's a possibility it is a macro deficiency(e.g. nitrogen, phosphate, potassium) as it's affecting older leaves first. If ferts don't fix that in a few days look into blasting oxygen into the tank, heavy surface agitation and maybe improved flow distribution...

 

[castle]

Tank is about 6 months old, so I think I'll stick in an aair supply, I have some TNC complete; probably add 5ml of that a week going forward, which seems about right?

 

[sciencefiction]

Generally, it could still be anaerobic soil but less likely in an older tank, especially if you've had some sort of stage when everything grows well....I'd add extra oxygen and increase nitrogen.

 

[castle]

Ahh, grows well, and growing are probably very different. A little concerned about substrate now, might be a good time to switch it all up and replant. Will see how oxygen and TNC go, if no noticeable change after a month, I'll be reporting back! Thank you 🙂