I have moved 4 pangio cuneovirgata and 1 pangio semicincta to an upgraded tank 5 days ago (I still have to move 6 more pangio cuneovirgata from the old tank to this new one). The first few days they had erratic behavior which was basically moving in circles like crazy and hitting a corner of the aquarium in perpetuity. Although I drip acclimated them for 3h during transfer, I thought it still made sense for them to be stressed because their new tank has different water parameters given it is a biotope tank ( 6PH instead of 7, 3GH instead of 5, 0KH instead of 1). In the previous tank they also had a period of stress when they were introduced almost one year ago, but not as intense as this one. Besides the aforementioned water parameters, nitrites are 0, there is no ammonum/ammonia, nitrites are at 5ppm, TDS are 140, aquarium is 1.5 month old, and temperature is constant at 25.5 celsius.

Discarded causes: 1. Toxicity: nitrogen compunds are negligible, but just in case I doubled the dose of Prime. There was no improvement. Like for their old aquarium, I use tap water, so things like excess copper or other heavy metals or chemicals are discarded. The pangios in my old aquarium are calm. 2.Disease: all my fish were treated for parasites, bacteria, and fungal infections when introduced to their old tank almost 1 year ago. 3. Aerosols/other chemicals in the tank: both aquariums are next to each other, both have open tops, and I feed the same 4. Environment: they have many hiding spots and have very small granule sand; the same as in the previous tank. The current is lower than in the old tank. The water has a lot of tannins.

Possible causes: 1. Excess detritus: this is a biotope aquarium so it has a lot of dead leaves. This, naturally, creates detritus in the water column. I wonder if this damages their gills. Today I cleaned my canister filter for the first time (1.5 moth) and removed a lot of junk, and added a sponge filter to the filter intake. 2. Copepods: I collected cyclops from the local river 3 months ago, and cultured them in a resurrection jar. In the 1.5 months of the aquarium their population has exploded. I wonder if too many cyclops are stressing the fish or getting inside of their gills. 3. Aquarium soil: besides a lot of botanicals and the copepods, something else that is different to my other aquarium is that in this one I used 6 lb of Tropica aquarium soil ( the aquarium is 24 gal), and have only floaters (my other tank has many plants and floaters, and innert substrate) 4. Kh: kh is 0 which would lead to ph variability. I check my ph twice a day and notice a 0.3 increase in the morning after using an airstone during the night. I wonder if this change in PH affects the fish. 5. Botanicals: I boiled all botanicals before placing them in the aquarium. However, now that I remember, I used the water I boiled the driftwood in, because it had a lot of tannins. Maybe the driftwood had chemicals or something?

Other notes: the fish are eating, and seem to be very excited when I feed them, as if they are very hungry. This surprises me as I thoughy they would eat cyclops.

My last hope, to see if there is any improvement, is using activated carbon. If this does not work I do not know what to do. Any help or advice is appreciated.

Thank you