This is what you get when you put money into unregulated exchanges. I think that there could well be huge amounts of criminal activity going on (just look at the Ponzi scheme Bitconnect, which has collapsed in the last week). At the very least it's a haven for money laundering, and if you make any large profits trading your bank will ask some serious questions, or refuse it entirely (the latter has already reported to have happened). People are having problems getting money out of exchanges, which raises the question as to their liquidity.
Tied to this, and even more worrying are the allegations surrounding Tether and Bitfinex. The following is information that is currently being discussed online (some of this I'm simply relaying what I've read):
For those that don't know, Tether is a cryptocurrency that is supposed to be pegged to the dollar. The company claims that investors deposit cash, and then they receive Tether in return, which they either keep or trade with. Because of the supposed 1:1 ratio, many exchanges are giving crypto prices in Tether, rather than USD. The terms of Tether state that you will not necessarily be able to transfer a Tether back to USD.
The problem is that Tether lost it's banking partners 9 months ago, yet somehow it is claiming that institutions are "investing" in Tether in ever higher quantities. They claim $500 million in the last week, to make the total $2billion. The company have not been audited to prove that they have $2 billion in their bank. Their last bank severed ties in 2017, and they won't name their new bank.
It would seem bizarre that institutional investors would put $100 million a day into a company that won't provide an audit, nor name its bank, in return for tokens that the company say they won't necessarily convert back to real USD.
The people who own Tether also own Bitfinex, a crypto exchange (this info came out in the Paradise papers). The allegation is that they are printing Tethers that aren't backed by deposits, in order to provide fake liquidity to their exchanges. They could also be manipulating the prices as well using this fake money. Certainly, if you look at the charts you can see areas which look like price manipulation. They could also be money laundering, or simply using the exchanges to sell people worthless Tethers in exchange for real US dollars, using the crypto currencies as a sort of arbitrage.
This isn't without precedent. It's been shown recently that the previous Bitcoin bubble and crash was cause by similar behaviour. Bots artificially pumping the price - Pump and dump. The main exchange back then, mtgox, did not have sufficient liquidity and lots of people lost a lot of money.
I'm not in a place to give financial advice, but if you have any money in exchanges please be sure that you will be able to get it out. Exchanges have gone bust in the past, and they are unregulated so don't need to provide evidence of their own liquidity. Be aware that any money deposited in an unregulated exchange won't be covered by the UK regulator, so if they don't give you your money you are pretty much stuck.
Further reading if interested:
www.bloomberg.com/news/articles/2017-12-05/mystery-shrouds-tether-and-its-links-to-biggest-bitcoin-exchange
(that headline is $814 million, it's now $2 billion a month later!!)