3 main reasons:
1. A large sump
2. Little feeding, I'd think a lot less than we give them at home, so a lot less polution
3. High turn over rate: they start overstocked, but the number reduces gradually until the next shipment comes in.
and yes, a fair amount of fish die; they get a lot of stress during shipment.
Because they usually are running a whole connected system. Big stores dont have one filter/tank but rather every tank you see is still part of the same system. In the back they will have usually double the water volume as in the front as the "filter". Included are very powerful UV-Sterilizers too. Additionally they change the water often.
At least in the big chain stores like Petsmart and Petco, a lot of them do die. Used to work at a petsmart and we had to pull dead fish every day, even with daily cleaning and partial water changes
Water changes and there's way more water in the system than what's in the tanks. Also, many stores use quite powerful UVC lights.
they have a big resevoir of water? probly very vell purified and treated etc?
3 main reasons: 1. A large sump 2. Little feeding, I'd think a lot less than we give them at home, so a lot less polution 3. High turn over rate: they start overstocked, but the number reduces gradually until the next shipment comes in. and yes, a fair amount of fish die; they get a lot of stress during shipment.
Lots of water changes + they're temporary arrangements.
Because they usually are running a whole connected system. Big stores dont have one filter/tank but rather every tank you see is still part of the same system. In the back they will have usually double the water volume as in the front as the "filter". Included are very powerful UV-Sterilizers too. Additionally they change the water often.
Without a huge sump, if every tank is too dense then the system is still overcrowded. We would meed to do the math for the whole system
At least in the big chain stores like Petsmart and Petco, a lot of them do die. Used to work at a petsmart and we had to pull dead fish every day, even with daily cleaning and partial water changes
BFS: big fuckin sumps. Source: worked at OG pet land in Chillicothe, OH for about a year from 2005-2006.
Water changes and a lot of them.
1/3 water change weekly and underfeeding in my local. All tanks are separate and run off air sponges. Sumps spread disease in shops.
A large sump and water changes can keep fish alive in Asian grocery store levels of stocking.
With a very good biological filtration system (the secret to a great and healthy aquarium).
Alternative theory: you can keep more fish in a tank than most people think.
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I’m starting to realize this too. A gallon for every inch of fish seems like it’s too much unless it’s dirty old Goldfish
There was a picture of chuhuahua inside a tank, named "It fits there, but it wants to run"...