Sword leaf edge browning

[JJenna]

I'm well versed in the care of plants outside the aquarium. Does anyone know if some of the same basic rules apply to aquatic plants? I planted Amazon Swords on 11/9/22. As you can see from the picture, I've already got a sword baby that I will cut off soon, but the leaf next to it has turned brown around the edges over a few days.

The roots of the plant look healthy, nothing is rotting. I've used a weight on it, could I be "choking" the plant? It likely isn't a drainage issue (the substrate is Flourite). Could it be a fertilizer issue? I'm cycling my tank with plants and use Easy Green 2x week at this point. I'm not using root tabs at this point. This is the only leaf that it's happening on. Can I cut off the brown areas, much like I would do with my houseplants without any problems? Or should I just cut the whole leaf out? 

Could it be my light? I have a Fluval plant 3.0 that is flush on the tank. It is centered over the back of the tank and currently, the settings are 30% pink, 2% blue, and 40% whites. It's only on for a total of 8 hours a day (with a 1.5-hour ramp up and down included in that 8 hours). The light was initially centered on the tank but the Xmas moss started growing hair algae so I moved it back.  

All of the plants are low light except for the crinum. Should I raise the light or place it more over the crinum? This is a 40-gallon breeder. tank. 

Thanks for any suggestions!

[TheSwissAquarist]

Amazon swords are a root-feeding plant (they absorb nutrients from the substrate) and fish poop will only keep them propagating and growing do so long. Easy Root Tabs would be a good course, unless the swords getting too big…😜

[JJenna]

On 11/27/2022 at 11:54 AM, TheSwissAquarist said:

unless the swords getting too big…

I have a few whose tips are out of the water. Will try root tabs again. Thanks for the reply.

[MattyM]

I saw Cory in a vid saying you really can't give swords too many root tabs. 

[JJenna]

On 11/27/2022 at 1:17 PM, MattyM said:

I saw Cory in a vid saying you really can't give swords too many root tabs. 

I've seen that as well! Just strikes me as odd that out of 6 plants only one leaf displays this. Should I just cut this leaf out? I don't think it will recover. 

[MattyM]

On 11/27/2022 at 12:23 PM, JJenna said:

Should I just cut this leaf out? I don't think it will recover. 

I don't think so either, but right now the plant might actually be taking nutrients from it. Maybe get some root tabs in there and then prune it. 

[lefty o]

that looks like an emersed grown leaf vs submersed. the leaves on the plant will likely all die off, and it will grown new ones assuming it isnt nutrient deficient.

[JJenna]

On 11/27/2022 at 7:38 PM, lefty o said:

that looks like an emersed grown leaf vs submersed. the leaves on the plant will likely all die off, and it will grown new ones assuming it isnt nutrient deficient.

lefty o, that make perfect sense to me, it's on the outer part of the plant!