Ficus (dying?)

So, I bought a fig tree about 5 months ago. Since Norway is a cold place, and this is a tropical I just assumed it had to be indoors.
It has been standing in my windowsill for the whole time. It was growing and looking quite well. I was watering in the same way all the time, letting the soil dry more or less, then watering it by submerging. And spraying it with a waterbottle if its warm. I have another fig that is standing even more in the sun and it looks ok. THe other one is a small tree and it grows very slowly now..
Well, back to the big one. The thing is, the last week it has started to lose the leaves. New shoots are appearing, but they dont grow much. The last 5 days, they have shown no progress at all. The leaves are falling off. I dont have many left. They are turning slightly yellow and falls off when I blow carefully at them. Even small month old leaves are dying. Shoud I get the tree outside? Or is it some other factor? Im posting some pics, but you might not be able to see them before the uploadproblem is fixed.

Any help is really apriciated.



-Storm

Have you been moving the tree around -- from window to window or from sunlight to no sunlight?

What kind of fig is it?

Its been standing on the same spot all the time.. Not much direct sunlight, because the sun is too high these days, but very lit.
I think its a Macrophylla, or it might be benjamina, the leaves are a bit pointy at the tip so I think it is most certain the last option.

Could it be because I have the window open more now than before? Especially at night, because it gets too warm here..

I am told that Europeans heat their homes less than we Americans, but if you were using heat in the winter indoors it might tend to dry the soil faster than this time of the year when I wouldn't think you would use much heat. So, if you are following a set watering schedule, with less artificial heat indoors the plant might be staying too wet.
Have you used a meat skewer/chop stick to check the soil?

I have, but normally I just push my finger into the soil, and when it feels a bit dry, I water it.. I dont use any heatenning inside the house. I has been a bit colder for some days than earlier, and I have had the window open. It also results in draft, so might not be so good.. Atleast its more likely to be over-watering than too little.

I don't know if this has anything to do with your problems, but watering plants by submersion allows minerals in the water to build up. Spraying from top down sort of washes the minerals out and "cleans the slate" at each watering. Here in Arizona I have a problem with calcium building up and solidifying my soil structure.

THanks for the advice! It could be some of the reason, though I dont think its completely because of it. I have seen white edges on the pots building up, I was told it could be salt, but I dont know. I can add a pic of my Elm which you can see it easilly.

You have "salt" deposits on your soil and pot. "Salt" in this case many not be the same as what we in America call "Table Salt."
I would suggest watering from above with distilled water and ease up on the use of fertilizer for a while. All commercial fertilizers contain "salts." If you are soaking your plants in a fertilizer solution, you are really creating a problem.

This site tries to explain "salts" in fertilizer.

www.algreatlakes.com/pdf/factsheets/ALGLFS15_Fertilizer_Salt_Index.PDF+Fertilizer+salts&cd=1&hl=en&ct=clnk&gl=us" target="_blank" rel="nofollow">http://74.125.47.132/search?q=cache:yjFUTiGSH3cJ:www.algreatlakes.com/pdf/factsheets/ALGLFS15_Fertilizer_Salt_Index.PDF+Fertilizer+salts&cd=1&hl=en&ct=clnk&gl=us