Of course nothing to stop you trying another pair combination in tandem Tanya. If pairs are working better for you then try combining them as it is likely that your pool of EAs for these pairs are higher quality (which can be partly lucky sometimes as it is very possible to run the reactor with exact same settings and pick top 10 the exact same what and one with far more overoptimised poorer quality EAs than the other.
This is one of the main reasons it’s important to test them appropriately out of sample, starting with using demo accounts (and patience) and progressing to using EA studio without the demo as your experience grows.