this could be nitrogen related, are you using a liquid fertilizer? honestly though the rest of the plant looks fine, just cut off the dying leaves comrade ✂️

I miss my fishtanks

probably low bioload if it's a shrimptank. Cherry shrimps are very hardy, if it's a mature tank you can probably reduce your water changes and don't clean your filter too often unless flow is heavily reduced. All that gunk in the media is good for your plants. I always had a sponge prefilter for my my filters and just squeezed them out when I do water changes, never touched the inside filter media.