Most people would love to have a spring-fed pond that stayed full all of the time. However, there actually can be some downsides, as you have discovered.

Do the springs emerge directly into the pond, or do they emerge from a hillside above the pond and then run across the ground surface and into the pond?

If the latter, then it would be possible for you to "intercept" the springs and temporarily pump or route the water around your pond while you did algae treatments or added pond dye.

If that is not possible, then you might read some of the threads about tilapia for some algae control. We have several members in your area that are quite good at managing their own ponds. If you started a new thread on tilapia for algae control, then you might get some good general advice, and some excellent local advice from your "neighbors".

Finally, the algae does compete for nutrients with the rooted aquatic plants in your pond. If you increase those plants, it will somewhat inhibit the growth of the algae. There are several types of water iris that might help in that regard, AND make your wife happier. You do need to research any plant additions to make sure you do NOT add anything invasive or fast spreading.

At this point, the grass carp might actually be hurting you in your battle against algae. They are eating some of the aquatic plants in your pond, and don't eat algae. How many grass carp, and of what size, do you have? If you list that and your existing plants, some of the experts might be able to recommend a better balance.

Good luck improving your pond! A 1.2 acre, spring-fed pond has the elements to become a real gem.