What kind of soil mix do you have it planted in, google 5-1-1 citrus mix and gritty citrus soil mix.

That's not a deficiency. It is a disease.

What growing zoe are you. Can you plant in ground.

Steve

Not a deficiency, but rather insect damage. Damage from a sucking insect that feeds on the juices of the leaves. Cannot see clear enough from the photos but probably scale. When the insect feeds it removes the chlorophyll from the leaf, leaving the yellow circles.

Thanks for the replies everyone!

@Ike Stewart - the mix originally was the 5-1-1 citrus mix but that was about 6 months ago.

@Efi Pavlos - What disease would you say it is? How would one mitigate it?

@poncirusguy6b452xx - I'm in growing zone 6a so unfortunately planting it outside is straight out of the question. I wish it weren't the case but oh well.

@Silica - I'll try to get some better photos posted when I get home from work. How would I go about getting rid of the bugs? Just use a pesticide?

Try a fungicide spray. I asked about zone to rule out HLB. If it turns out to be HLB the seller and county extension agent must be informed by you with where the tree came from.

Steve

I also think it's insect damage. That is exactly what happened to one of my trees being attacked by scale and mites in years past.

@Gavin Nugent I cannot be sure from just a photo, however it looks like an insect infestation.Try to examine your leaves .

Alright, do you think a horticultural oil will take care of bugs?

The big 4

Africa has what is know as the big 5.

lion, leopard, rhinoceros, elephant, and Cape buffalo. These kill humans instead of citrus trees

Good to also own if you don't already, old fashioned insecticidal soap (you can tweak this add a dash alcohol/peroxide (should own) dependent on situation, cheap and great indoors/outdoors