New tank issues

[Linark2001]

Hi everyone. Im very new at fish owning and i have a dilemma. I had a 32 litre tank set up with one male betta. all readings were 0 and ph was 7.6-7.8 (which is the levels out of my tap) after a month my betta got finrot. I went five days treating him with pimafix i decided that i will get him a bigger tank as the water wiĺ be easier to manage. I got a 2ft tank (around 66 litres) i used about 20 lutres of his old tank water, and the filter and plants feom the old tank. I did get new substrate and added a new sponge filter to the new tank. So i bought 3 small albino corydoras as tank mates for him. 1 day later i tested the water in his new tank and 0 for all readings but ph has plummeted to 6.4. I cant underatand why? what should i do iz it a safe level for my fish and should i continue to use pimafix (not sure if dangerous for corys) or see if cleaner water will heal the finrot. Sorry about the long boring rant

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[sinibotia]

What is your water hardness? Specifically KH? That's the real important factor behind pH.

 

[Mebbid]

The only problem I'm having is with all the readings at 0.

This should never happen unless the water is brand new out of the faucet. What test kit are you using? And are you following the directions to the letter including timed shaking of the vials?

 

[Linark2001]

Sorry. I mistyped. I only have an amonia and ph test here. ammonia is whats at 0

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