wrote in message
...
Dick wrote:
Just a personal bias, I prefer more frequent changes and less
percentage. I go twice a week at 20%. The bacteria that are
established during the first "cycling" are what maintain the tank's
health. I know I have read others that make large changes, I just am
more comfortable to leave a larger percentage of "old" water and the
bacteria in that water.

Bacteria client the surfaces in your tank / filter. Water changes won't
remove your beneficial bacteria.

I can vouch for this: two days ago I added a 1M length of clear pipe to the
outlet of my main filter to do a small experiment with water movement.

The experiment finished today and I removed the pipe - the pipe was slippery
slimy - that was the bacteria in the water column - amazing really

Oz

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