Seemingly Dying Java Fern

[Summer Lotus]

While I was cleaning my sponge filter today, two leaves from my java fern came off. There's a lot of black spots on the leaves. Is it salvageable? Is this a light issue? A potassium deficiency? Granted, I haven't been able to use a proper light because my betta fish can see himself in the glass and keeps flaring. He did it for 3 days and shredding his fins. I ended up turning off the light except for the blue light for the past 2 weeks while the betta fins heal. I'm also afraid all of my other plants will eventually die if I can't use a light. Would appreciate any suggestions.

[CoryWithAKatana]

What is the wattage or your light? Java Ferns like medium/low light. This could also be a melting issue/ its new to the tank so its shedding some leaves as it adapts. Or it could be those are old leaves, and old leaves make babies! In the attached screenshot it looks like a root is coming off of the leaf (bottom right, its kinda blurry) , look underneath the leaves and you might find a baby java fern! They should fall on their own but you could VERY GENTLY try to take it off with you fingernail. If there is force when you try prying it off dont continue as this could prematurely take it off the mamma plant. 

What is you fern attached to? Is it buried? Glued? Tied with string? 

Also lets test the water for Nitrites/Nitrates/ammonia/etc.

Edited August 12 by CoryWithAKatana

[Summer Lotus]

I think the light uses about 13 watts. I haven't been able to use the light completely, maybe just 3 days. All the other days have been blue light only. If the java fern leaf comes off and they're still green, should I just leave them in the aquarium? I'm afraid the loose leaf may melt and cause an ammonia spike.

The fern isn't attached to anything, and it's definitely not buried. Should I get rocks or driftwood so it can attach to something? 

I checked the water parameters shortly before doing a water change. Ammonia and nitrites have been stable at 0 ppm and nitrate was about 5 ppm based on the API test kit.                                    

[CoryWithAKatana]

On 8/12/2024 at 5:49 PM, Summer Lotus said:

I think the light uses about 13 watts. I haven't been able to use the light completely, maybe just 3 days. All the other days have been blue light only. If the java fern leaf comes off and they're still green, should I just leave them in the aquarium? I'm afraid the loose leaf may melt and cause an ammonia spike.

The fern isn't attached to anything, and it's definitely not buried. Should I get rocks or driftwood so it can attach to something? 

I checked the water parameters shortly before doing a water change. Ammonia and nitrites have been stable at 0 ppm and nitrate was about 5 ppm based on the API test kit.                                    

your water seems stable. I also have 13w light and mine do fine, maybe wait like a week with your light on and see how it does. But make sure you have your light on for 8 hours or less, you dont want pesky algae to grow.

I would 100% take out detached leaves because you dont want them to rot/create mold in your tank