That could be the reason why the Etheruem is so popular. The trading volume of Ethereum is higher than bitcoin some times.

The trading volume of Etheruem has reduced quite a lot recently. That is mainly because the Monero is more popular.

In fast, the trading volume has increased gradually. In Poloniex, it is about 14,000 now. The Monero is 11,000.

They have both dropped below 10,000. the Ripple has the highest trading volume at the moment.

The Monero is still the largest trading volume in the Poloniex. It seems it is the most popular coin at the moment.