According to my opinion, the Alternate cryptocurrencies Price will down for a while because ETH and BTC getting strength in this month. If we look at the depth market in all exchanges, especially Altcoins/ETH or Altcoins/BTC, you will see the contrast, supply and demand is not equal. Most of people converted their coins to ETH and BTC.
Here is some examples:
HitBTC Market:XMR --> BTC

BSTN --> ETH
Indodax:
What do you think? Lets we discuses more. Cheers
not all altcoin decreases as bitcoin and ethereum increase. all of that has been proven in some time ago when bitcoin rises then the market turns to average green.