Altcoins pumped to in march but then dump in April. I saw many good altcoins dumped. But when bull season start, they'll obviously raise up from their position.
I don't know how long you've been in this industry but I can tell you that what happened in the period you pointed to was just a spike, not in anyway a pump. Wait for the pump once Bitcoin market dominance drops and then you will experience what it's for alts to pump. It's always a crazy movement where unbelievable Xs are done. As for now, it's far from being alts season. Bitcoin still has half of the general market cap.