i never subscribe with zulutrader before, just an ordinary registration. there's many site offer similar service, but i would suggest myfxbook, they have solid rule for autotrade provider, disadvantage is not all brokers all supported. I plan to register as autotrade provider using my current ECN account with Armada Markets, which their platform support myfxbook autotrade feature.
here's their requirement for autotrade provider :
A connected real and verified MetaTrader 4 account with Myfxbook with at least 3 months history.
Drawdown of no more than 50%.
Return of at least 10% and higher than drawdown.
Average pip win per trade of at least 10.
Average trade time over 5 minutes.
System must not use any martingale/grid techniques.
An account balance of at least $1000.
At least 100 trades.
with this rule i believe you will find positive on your copy trade activity. good luck.