Help id amazon sword deficiency

[sobersteve323]

Looking for help IDing this deficiency in my amazon sword. Is it nitrogen or magnesium or?

T5ho 56w (timer set for 6 hours a day; ~18 inches from substrate)
50 gallons
Eco complete
Root tabs
Excel
No other ferts
0 ammo
0 nitrite
5-10 nitrate

Thanks guys.



Sorry if its a poor pic using a phone.

 

[sobersteve323]

Additional info:

Yellowing started at the tips of 3 leaves yesterday. By this afternoon most of the affected leaves were yellow. A 4th and 5th leaves are now looking yellow at the tips.

Also, I recently changed substrates a few days ago. The sword was exposed to air for a couple of hours (the swap took longer than I anticipated and forgot about the bowl of plants sigh). Could they be dying off due to drying out?

The plant has a new leaf already since Monday. Maybe its shedding older growth from the substrate change/long exposure to air?

Thanks again.

 

[bluebirdnanny]

Yep, I think you already figured it out. Air and substrate change. Clip the old yellow and new will regrow.

 

[sobersteve323]

Yep, I think you already figured it out. Air and substrate change. Clip the old yellow and new will regrow.

Sounds good. Thanks for being reassuring lol. Only got worried when I saw how fast the first 3 leaves were dying off.

 

[aqua_chem]

Could also just be pouting from the move.