crypts how big will they grow

The brown/bronze C. wendtii cultivars are highly variable for me. Some of them can exceed a foot high. The cultivar 'Tropica' is the smallest I have.

For me, the wendtii variants are the most resistant to melt.

As said by others, they fill in nicely but not fast by runners. The wendtii is modest in runner length, so tends to nice thick stands, but it does take a while to develop. Some other crypts throw much longer runners.

C. lutea stays about the size of the smallest wendtii cultivars for me.
 
big crypts lutea and wendtii

In my tanks the crypt wendtii red is about 14 inches tall in 15 inch water column and the lutea is 19 inche tall in a 15 inch water column.

I've had each for just over a year. The lutea came from a single pot from PetCo that I split into 3 stands, it was very small then, maybe 5 inches tall with leaves 1/4 inch across. After about 9 months I had to bulldoze the plants to the back of the tank as they had outgrown their places in the front. Now they drape over to the front of the tank, leaves 1 inch wide and olive green to brown.

The red wendtii arrived as 3 bare rooted plants, each about 8 inches tall with 1/2 inch wide leaves. It had one year in the 20 gallon tank and developed many offshoots and filled the corner. then I moved it to the 59 gallon, ini a spot with good flow and much brighter light. It is super thick and after only 2 months really needs thinning out. the leaves are very much lik ethe lueta but more ruffled and much more brown-red.


I suspect that the height is dependant on lighting, the low light tank has the taller crypts.
 
The LFS said that you can detach segments of new growth (break or cut it off). There is normaly that little rooty nub the plant grows from... as it grows and spreads the little root thing grows nobs. When you split them, you should have a small number fo leaves on the new growth before splitting.

...at least this is what I was told.

I did do it to one plant that I bought (it was applicable), and everything seems okay (been a week+ since doing it).
 
I agree with RTR, I have a red wendtii right now that is 12" tall. There is no way they will stay 6".
 
AquariaCentral.com