What Is This Plant And Whats The Best Wasy Of Gettin It To Grow?

[cheesy feet]

looks lide d. riccia or something.If it is it must be tied down?

Riccia does 'not' need to be tied down; It is a very good floating plant. However, if tied down, it can look excellent (if given the right conditions, of course...)

What i ment is for it to be like that it must be tied down

 

[George Farmer]

It's Riccia fluitans. Not the dwarf variety.