Plants in the pond consume nutrients and usually compete with filamentous string algae(FA). Generally, the more higher plants that are present the less FA persent. Without competition for space and nutrients FA thrives on all available nutrients that are present. Newly exposed dirt almost always has nutrients leaching out of it to grow weeds-plants. The more the dirt is compacted the harder it is for many plants to get rooted.
Submerged plants provide the most competition for FA whereas the emergent shoreline plants stabilize the shoreline to reduce erosion and compete with other nature's introduced plants that can be a nuisance if not managed. Some common good emergent plants are water iris, spike rush, pickeral plant, lizard tail, dwarf cattail, some Juncus. IMO the best deeper water plants are hardy hybrid water lilies in the dwarf, small, and medium size ranges. I don't recommend water lilies in the large category that can grow 7-9ft deep unless it is a lake.
This from the Archives will get you started learning about pond plants. There is also a thread in the Archives about water lilies.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=440475#Post440475Introducing water from an established pond can be beneficial providing the donor pond does not have various algae issues esp in mid-summer. Ponds do develop a natural micro-organism community - Nature is amazing about introducing zooplankton. Try not to introduce problems that can develop later. A general good time to move water is when the donor pond is clear. I always check the algae and zooplankton community for species composition before adding any water to a pond. Otherwise it is a "crap shoot". A receiving pond with out fish does not need very much water introduced (1-5gal). The "bugs grow quickly even in colder water. If the donor pond regularly received chemical treatments/herbicides often the beneficial micro-organism community is compromised. Fish species present will generally determine the structure of the zooplankton community. Certain fish species such as small BG, crappie, and lots of abundant minnows heavily graze on larger zooplankton changing the species present, especially consuming the larger species that are selectively grazed. Ponds with dense or significant amounts of cover provide refuge & habitat for zooplankton. The ponds that have just LMB is where I get the best water and zooplankton. These ponds are generally quite clear. Bass >4"-5" long rarely eat larger zooplankton (Daphnia - Diaptomus) thus those ponds have lots of good large zooplankton species. Note that the species composition of zooplankton will often be different seasonally.
Structure does interfere with dirt work in a pond.
