What's wrong with my Fiddle-leaf fig?

[PitcherPlant]

Hi!! A few months ago I got this little baby fiddle leaf fig from a random plant store. It was in a 4-inch pot and had maybe 5 leaves total, but looked healthy.
Since then It's grown lots of new leaves, BUT, and this is a big but, the leaves all have those little red freckles (edema?) and get smaller and smaller. The leaves stop getting bigger when they are only a couple of inches long now. I know I'm not overwatering it because it's in a smaller pot than the rest of my plants and I have a bad habit of forgetting it. It's in a south-facing window, so could it be a situation with too much light? It doesn't have any brown or yellow spots, just red freckles and leaves that keep getting smaller. What am I doing wrong?

 

[Marck]

Greetings, welcome to the Forums.

If the red spots are edema,it may if watering and soil moiture is maintained more evenly. Both underwatering or overwatering can cause an edema reaction.

Leaves coming out smaller could be due to cool temperatures or low nutrients. Try feeding lightly now with a complete, liquid fertilizer and again in Spring when more light may make the plant's growth rate increase.

If possible, post a picture of this damage.

 

[PitcherPlant]

 

[PitcherPlant]

Its kinda hard to tell in the photos, but all of the recent leaves had the little red freckles, including the one currently starting to grow. As the leaves matured the freckles became less prominent. I stopped fertilizing the plants when I started giving them some high-nutrients aquarium water whenever I had some left over, which is constantly. Probably not the most balanced system, so if that could be part of the problem then I'll change that. I don't think temperature is the problem, but underwatering is definitely a possibility. Thanks for the feedback!

 

[cpp gardener]

Aquarium water is great for plants. Keep using it, but watch the moisture level of the soil. It will tolerate moister soil levels in high light conditions.