I'm quite postive it's Egeria densa (aka Anacharis Elodea, Pondweed). Easy to keep but they won't stay anchored, they are floating plants. Somewhat sensitive to high temperature it usually does best below 79F (26C). It can grow up to 20 inches and prefers hard water. Be careful not allowing cuts from this plant into natural streams of water since it can become a pest. As they grow you might see shooting filaments of roots coming out of it.
I wouldn't worry much about the white spots. If you do, remove them and give them a 5 minutes bath in 1:19 mixture of unscented
chlorine preparations (e.g. Ajax, Clorox) and water.
Pepetj
Santo Domingo