Wyatt - You mention "My concern is that there are to many bass and to little of the smaller crappie and bluegill."
Keep in mind that BG and crappie can be and usually are very prolific. As you read more info on this forum you will come across info that indicates Crappie (BC - blk crappie) are bad for a pond because they are usually or often over abundant and not larger than 6"-8". In situations like yours where bass are smaller and abundant most all reproduction from BC and BG get eaten by the bass thus leaving a relatively few BG -BC that become large. Thus in your situation as you start to remove bass from the pond the numbers of BG and BC will gradually begin to increase and the catch records will show this -more and more smaller panfish caught. Previous posts here will explain how many bass to remove per acre. Also records should show anglers are gradually catching a few larger bass. When that occurs things are moving in the right direction - more panfish, fewer & larger bass. This is why you and others that fish your pond need to keep catch records - to see the trends over time.
?? 1. How much moss. Well, that is a good question. Ponds have moss. Generally ponds in the northern areas with limestone based soils with clearer water tend to have more moss, aka Filamentous algae - FA. Fertilizers and natural recycling nutrients feed this moss. Another generalization, weedier ponds have less moss -FA. Submerged weeds, plant plankton and FA use and compete for the same foods -nutrients. One often dominates at the expense of the others. IMO a coverage of FA more than 30%-35% in spring or summer is too much. Most prefer no FA but that is not realistic; also I prefer not to die and that is not realistic.
You will not need more grass carp until submerged rooted plants cover over 25% of the pond's bottom. Then think about adding more grass carp. Grass carp do not eat very much if any filamentous algae (aka moss) - it depends.
Ewest covered top concern #2. IMO your top concerns are to do the home work ewest & I gave you in the earlier posts.
Does your pond have a drain?
What is the overflow like? Spillway or pipe?
