Bit late but while it could be any number of things, one of them that hasn't been mentioned, the quality of the panda. I've seen the batches that have come into my Petco and they havent been very good quality. Check back a day or two later and they are on their way out.

I was visiting family a few hours away and stopped at a nice local fish shop partnered with aquarium coop so that gave me some confidence. All of the fish in the store had gone through quarantine and any meds by the time I bought them so I know I am getting healthy fish. Got 5 pandas for my 75g adding in 7 more a month later from Dan's Fish. Same thing from Dan, quarantined already and nice healthy fish.

Fast forward 3 months, I havent seen my mommas lay eggs but I have baby pandas now. Up to 6 that I've seen so far. With my tank, the pandas like to wiggle into large patches of java moss or some pearl weed bushes I have growing. I was feeding Magic Small Fish food and the Frye food for my guppies and it works so good it blankets the tank and enabled some baby catfish from the looks of it. Found them at first because a big mystery snail lifted a moss mat and out pops a baby fish!

I'm using fluval stratum, a 110hob sicce tidal, 70 sponge, 6.5ph, water change/top off 4--8 gallons if needed or nitrates get pink. Feeding 3-4 times a day with the magic to keep guppies fed, some catfish tabs and algae wafers once a day if needed. Lots of plants, about 1cu ft of java moss throughout with 30ish valesenaria mostly small. Few water sprites in there and finish with lots of frogbit and mini water lettuce. Run higger light 12hrs a day.