EA testing

I have tested an EA in the tester and with broker one it make a profit of 2k/year and with broker 2 a loss of 2k/year with same settings in the EA and tester why?
Have you checked spread, commission, swap ect?
I use fixed spread in the tester

Generally the result of an unstable system, or possibly bad data.

Each broker has their own data; it should be broadly similar but there will be differences.

Maybe different opening time too. You aware of Sunday candles?