Carambola Grown Indoors

This starfruit was grown from seeds and is less than one year old;however, the seedlings has grown pretty quickly reaching almost 1 1/5 ' . I currently have it growing inside to overwinter. However, I've noticed some strange light spots on the leaves.

Does anyone know if this is disease related or environmental stress?

 

Not acquainted with the plant, but if I saw that sort of dusty/spotted look on anything else, I would assume spider mites. Can you get an in-focus shot of the undersides of the leaves?

 

My camera is not so powerful. This is the the closest I can focus the picture.

 

Here's a picture of the underside.

 

I think I'm comfortable with diagnosing spider mites, based on both photos.

 

Thanks mrsubjective. I'm going to agree with you on your diagnose. I googled the images of spider mites infestation on leaves and believe this is what I have. Along with your confirmation, I think we're both correct - but I couldn't have done it without your help.

 

You may have trouble keeping this as an indoor tree. I had one which I tried to keep small through pruning but there was no stopping it from becoming a tree. So unless you have a large area... It is an interesting tree to grow though; the leaves fold up at night.