With fixed voltages you use wire speed & torch speed (technique) to control the puddle. Sounds like you wanted the torch to run hotter so you should have moved faster to counter the heat.
A good weld sounds like bacon sizzling in the pan.
When all else fails, read the instructions!
My welder has a guide on the lid: Material thickness, voltage & wire speed settings for solid (c25) & flux core wire. Setting the machine to their recommendations before starting means minor wire speed adjustments at most.