it is due to everyone wanting to buy bitcoin. there is a bitcoin hardfork coming up Oct 25th for Bitcoin Gold. If you have Bitcoin on Oct 25th you will also get air dropped the Bitcoin Gold.
Bitcoin Cash the highest it went to was 900 each. Bitcoin Gold could make you some nice money
Exactly Bitcoin price is going crazy right now because of the hard fork.
For the reason why Altcoin price are dipping it is simple more people are buying Bitcoin therefore fewer people are paying attention to altcoins. Money flow are going to Bitcoin. Right now since basically altcoins are in sale i am accumulating more altcoins. I honestly think that getting altcoins will surpass my profit if i buy bitcoin and wait for the fork.