Cycling new 50gal

I actually prefer buckets, but my tank is only 30 gallons. A friend of mine has a python, but it seems to waste a lot of water and involve either a) a partner, or b) a lot of running around.

And it sounds to me like as long as the media you are putting in the new tank is established in the old tank, the pleco should be fine. It sounds like your plan for testing/changing is a good one. After all, one plec in a 55 isn't much of a bioload to begin with.
 
I would wait a little longer between your first and second fish just to make sure your filter is cycled but after that, as long as they are somewhat small, that sounds fine.
 
As far as the python goes, it's been great for ADDING water to the tank, but to try and control waterflow the other way has just been impossible for me. It wasn't a big deal for me to use a bucket with my 10 gallon but I really hope I can get a hang of it with the 55. Gravity is a *****, pardon my french
 
you'll get the hang of it, i'd deff wait a lil longer after the first fish as mentioned above, just till you are sure the tank is cycled, after that, one a week is fine.
 
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