Suitable enclosure for L3 S. aurea?

[nzxmUyZNKEBoqN3e]

I got a tiny S. aurea about a week ago - he came as an L2 and already had a moult with me a few days ago. I'm wondering if I can still keep him in this deli cup - it's about 4cm deep and he is ~1.5cm long. I'll be removing the stick when he gets closer to his next moult, but I'm still afraid that it could end up being too small for him. My only issue is that the next size deli cup I have is one of the 32oz ones which is 15cm tall - I imagine this is pretty unsuitable for him!

Imgur link

 

[hibiscusmile]

He is good till he needs 3 times its height.