~ I'm mining the zcash with the console using nanopool for mine, but today 03/08/2018 I'm trying miningpoolhub and I'm liking the result. It seems like I'm mining faster than nanopool
It is ok to change pools and trying to find the right one. So as long as your happy with you pool choice, everything's ok.
one thing I'm seeing, when I started mining zcash it was $ 430 and bitcoin was $ 11200 and now zcash is $ 320 and bitcoin is $ 9600, is this normal? to descend so much? Is it still advantageous to continue mining? I'm afraid that the coin I'm mining (zcash) will die
Fluctuation of cryptocurrency prices is normal thing, you will get used to it in time. This are hard times for miners, but if you are already in it I guess you should continue and try to make profit out of it.
If you are convinced that zcash is going to die, than consider possibility of selling your savings and move to different coin. But don't let your emotions cloud your judgement, think carefully before any decision.