Some things transcend practically the entire fishworld. Water changes, for instance.
It doesn't matter if you keep a mud shark or a molly: you change the water.
Then again, the methods are another matter.
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"How to do a water change in a 2 gallon tank with 200 guppies"
1. Get your best guppy net & wave it around in the stinky guppy water.
2. Put empty net in a 10 gal tank holding 8 gals of water and age 2 days.
3. Pour the 200 guppies and 2 gals water into the 10 gal tank.
4. Let the poop sink.
5. Pour back 200 guppies into 2 gal tank.
6. Miller time.
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If you don't need a huge change, or cannot lift 200 guppies (in 80lbs of water) a 5g may sub for the ten.

It doesn't matter if you keep a mud shark or a molly: you change the water.
Then again, the methods are another matter.
.................................................................................
"How to do a water change in a 2 gallon tank with 200 guppies"
1. Get your best guppy net & wave it around in the stinky guppy water.
2. Put empty net in a 10 gal tank holding 8 gals of water and age 2 days.
3. Pour the 200 guppies and 2 gals water into the 10 gal tank.
4. Let the poop sink.
5. Pour back 200 guppies into 2 gal tank.
6. Miller time.
......................................................................
If you don't need a huge change, or cannot lift 200 guppies (in 80lbs of water) a 5g may sub for the ten.
