I'm new in cryptocurrency.
Have been lurking this forum for last week and also did my first investments.
I have invested in:
GNT
GAME
STRAT
TRST
SC
WAVE
I bought them at Poloniex and Bittrex. Is it safe for now to store them there?
Or should I store them in separate wallets? I'm new, so It would be harder for me as I have to create a new wallet for each currency. Or is there any other safe alternative that can store everything? I have heard of Jaxx.
Also, you can discuss or suggest me about my invested altcoins. Do you think they are good? I have profited from all of them for now except for GAME cause I bought it right at the highest bump for about 3$ and then the big crash/dump happened when everything hit red. I, of course, didn't know about that would happen cause I started to read about crypto on that day, lol.
Any tips are welcomed

It is relatively safe but there is still that risk that they declare they have been hacked. But since most of them exchanges nowadays use coldwallets this lowers that risks but hey look at what happened to bitfinex. They still say "they got hacked," which is hard to say if it was true or not as they can just pin it on a hacker and it may have been just them.