F2pool is a Chinese multicurrency mining pool founded in 2013. Now it has servers located in the USA, Canada, Russia, Singapore, and several other countries. The pool has a big number of supported coins. Currently, it is possible to mine around 40 currencies on F2pool.
UniPool is a BCN, TRTL and XMR mining pool. With servers based on U.S.A and Europe.
If you need, on Discord, UniPool team can help every new miner to start mining.
HashGains - is an enterprise of the American company Futuristics Internet Services that was launched in 2017. HashGains includes more than 1,500 professionals in their field, but also several mega data centers.