Orlando United has quite a lot of information on Volcano Bay and as always Teebin and Jungle Skip (the insiders) have released some interesting and very exciting details.
Jungleskip has said
"As the sun goes down, the volcano will erupt as it does during the day, but this time it will be more powerful/violent. As the geyser erupts, this time it's "lava", not water. As it cascades down the mountain, it turns all the water in the park to "lava" (done with LED lighting and stuff like that). At this time the park's background music and effects change to match the new "dangerous" setting"
This could potentially be an amazing visual effect and could tie in with the beach visual effect patent as the whole beach could turn lava red.
The only piece of news that has been released is the that the park is due to get a "HydroMAGNETIC MAMMOTH" slide which is an LIM launched slide, more information can be found here