I have looping underneath. Top stitch looks great.

Your description isn't very clear. When you say the "bottom stitch is using too much thread" Do you mean you see lots of loopy threads on top of the seam? Or do you mean you see loops on the bottom under the fabric? If your loops on the bottom, that means the top tension is too loose, you've not remembered to put the presser foot down, you have not threaded the top thread properly... Start by rethreading carefully with the presser foot UP. Then do a test stitch, remembering to put the presser foot down. If you still get loops underneath... tighten the tension.

If your loops are on the top of the fabric. loosen the top tension... then do a test seam... and if you still have loops loosen again and repeat. If you start to see loops on the bottom... tighten the tension a bit.

Good luck

have you tried changing the needle?
have you tried adjusting the top tension?

try adjusting the top tension one number or letter higher till the stitch looks normal
change the needle

change the needle
adjust the top tension one number or letter at a time higher till the stitch looks normal
check to make sure the bobbin is inserted into the bobbin case correctly

check that you have threaded it right

Usually If the underneath is loose it is the top tension that is the problem. If it is the top stitching that is loose it is the bottom tension. Hope this helps.

FYI---- Loops on the bottom-- problem is in the threading..
Loops on the top--- problem is with the bobbin.

Rule of thumb..
Loops on the bottom ,problem is on the top.
Loops on the top, problem is on the bottom.
Tension should be set on the midway point making sure the thread is between the tension wheels.

I believe stitch 11 is a zig zag so you are probably decreasing the length to get a satin stitch. You will get a better satin stitch if you select it directly. I think that it is about 29. The machine forms the satin stitch differently than the zig zag and it should look better. If you still get loops on top, you may need to have a qualified technician check the needle to hook clearance. If this distance is too great, the machine skips stitches and you will form loops. Several other adjustments may be needed to get a perfect stitch and a qualified Husqvarna technician should be able to take care of this problem for you.

Sometimes when I need to use heavy thread for top stitching to reinforce a seam that has come undone, I will use the heavy thread on the top and regular thread on the bottom. I haven't tried it the other way around for hemming but I would think it would work. I do not currently have a Bernina.