I set up a 37 gallon freshwater tank a few weeks ago and have been running into a few issues that have stumped two pet stores and myself. I started with 3 neon tetras, 3 black neon tetras, and some live plants. I acclimatized the fish and plants prior to release into tank and each day I found a new dead fish at the bottom of the tank or stuck to the filter. I treated the water with dechlorinator prior to adding fish, by the way. I ended up with 2 neons and one black neon tetra. I brought a water sample to be tested and was informed that it was perfect. I waited a couple weeks then got a small Cory (forgot what kind, but it is supposed to top out at 3″), a small bristle nose pleco, 5 neons, and 5 black neons. Two days later I found 2 dead neons and 2 dead black neons. Brought them back for replacement with another sample. Again the sample turned out perfect, but over the course of 3 days I had 2 of each die. A week later I added a banjo catfish and a dozen ghost shrimp to help the Cory and pleco out, but the banjo ate half the cleaning crew (shrimp) overnight, which I kinda of expected. No fish died and I thought I was good. Then I turned off the lights, read my kids a bedtime story, and noticed a black neon tetra in its death throes at the bottom of the tank. It was less than 10 minutes from lights out to dead fish and I can’t blame the banjo because it still had its head buried in the sand like an ostrich from his morning. What the heck is happening to my tank? I would have been more comfortable if my banjo was eating the fish instead of them just dying for no discernible reason. No sign of disease, heater set to 75F. Some light whitish fuzzy stuff on glass that seems harmless from everything I have read. Any ideas?
d259- r Baja Boat Fishing Logo Neon Light Sign
Someone correctly mentioned about forest fish coming from dimly-lit waters. Neons were impossible to spawn in aquaria for decades until it was discovered they needed total darkness. The eggs will not hatch if any light hits them. Cardinal tetra are the same, and many forest fish. That tells us something about light levels in their habitat.
Pictures: Fish Light Up in Neon Colors - National Geographic
Donning scuba suits and special observational gear—all custom-developed after months of trials—the researchers submerged from the research vessel Alucia. They saw the pristine reefs as few people have, but many fish do: spectacularly aglow in neon colors. This phenomenon, called biofluorescence, is stimulated by the ocean’s ambient blue-light environment, visible only to those equipped to see it.
Fish Swimming In Aquarium With Neon Light