when the market is strongly fluctuating, I need your advice to invest mid-term or short-term in altcoin, give me coin names and reliable information about them, tks u so much :*
Forum population has quite significant range of opinions and tastes, but it doesnt mean that it can fit yours (if you care of course, and not just blindly follow someones choice).
I would suggest to open Coinmarketcap and to check within top 50 coins - historical data (prices, volumes), project websites, useful links in social networks etc.
For example you will see that suggested ICX is currently did not fell a lot from its ATH (comparing to some other popular coins)
Spend few hours of your time and you will have more or less clear picture about top projects.
Most people have those coins in portfolios.
PS.
Im using current dip to add more ADA and XLM to my portfolio. Maybe CND if it will fell for ~15-20%.