Should you buy? or you should just wait until it goes down further? but it might go up so you might lose the chance to buy right now, so in easy said, it is really hard to give a suggestion in a matter of buying or selling because in this cryptomarket everthing happens in so fast, like going up in a massive way then goes down again quickly, I suggest you to buy base on your own judgement of the situation.

Possibility is really high on that matter, since that not all of the altcoins will provide some real substantial use in our world, and also will not provide any good benefits, as you can see in the current time, there is a lot of altcoins with redundant usecase that just came from one another hence making it not really needed as there is the first one the provides that same use.

There's a lot of altcoins worth buying, but it's hard to suggest what altcoin would you buy since it is an investment and this will be crucial in your life because it involves money, but I do suggest you to look at the top coins in the coinmarketcap, this will give you some beautiful idea of what altcoin is worth buying by comparing them to silent coins.

Ripple XRP is really a good coin, but nowhere near Ethereum as of now, it will be interesting if XRP will provide something bigger that will surpass ethereum in any case but as of now, it's impossible for xrp to called better than ethereum just like that, they still need to beat the ethereums technology.

Obviously altcoins became famous when the altcoin season happened in 2017, this is where everything in crypto boomed and make a shower of money, happy moments of crypto. There were a lot of people attracted on people who made such a big amount of money from here, just like myself when my friend told me he earned a lot from bitcoin mostly from altcoins.

I am not an expert, but holding depends on what coin are you holding, if it is just another shit then just sell it right away before it's too late to sell and you will lose some money, but if you have some reputable coins like bitcoin, ethereum, xrp, etc. I suggest you to hold, there's a bright future ahead of these top coins, just choose wisely and most important, be patient.

The current market condition in 2019, the condition in this year is currently in going in a positive manner thus in this situation if there is any, holding your coin is the best choice in the way that I see it since I do believe that bitcoin cryptocurrency market will go bullish when the bitcoin make it's move.