[-Sutekh]

Hello everyone!

Coming to you for some help!

Please don't mind the horrid algae... I was experimenting with lighting and lost. It's been reverted back to the setting that had no algae and a 6 hour photo period until it stabilizes.

That being said, I actually recently had a few of a small school of fish die off, and didn't replace until recently. This actually happened around the same time as my lighting situation. That being said, I actually have another problem. I noticed the Nitrates are really low in the tank despite not really doing water changes. I am assuming this was due to losing the fish and not replacing the bioload. I'm working on getting Nitrates back up (less than 5ppm or maybe even 0 ), but I wanted to know what these leaves appeared to you as.

Are the examples below just nitrogen deficiencies?

Something else?

Outside of adding more fish and food, do you think it would be beneficial to dose Nitrogen in this case until it stabilizes? How much do you suggest if so?

Thank you!

 

[Roboto]

Could be macro deficiency of which nitrogen is one of the three with phosphorus and potassium being the others.
Keep an eye on your ammonia and nitrite as you may have lost the cycle of your tank if it was without any livestock for some time.