Tall grass? Eleocharis Vivipara vs E. Montevedensis vs Vallisneria Nana

[DennisC]

Looking for a somewhat tall (~15"), straight-growing background grass. I'd like something whose height I can trim without it branching or browning.
Considering Giant Hairgrass but I find it hard to differentiate between E Montevidensis and E Vivaparis. Some Vivaparis pics show it straight & clean while others show it looking wirey with what appear to seed heads at the end of the stalks, which I don't want. Do these eleocharis take routine tank maintenance with breaking or are they brittle?
V. Nana looks good too but my experince with common vals is, once established, they take a lot of work to control runners.
Comments?

 

[Allwissend]

E. vivipara will reproduce like that and can be cleaned but requires some degree of maintenance. E. montevidensis has that clean straight look you want but can grow a bit out of a tank your size and cut leaves will eventually be lost. Cyperus helferi might be another option or Sagitarria subulata. This last one will send out runners like Vallisneria spp. but even when it grows tall (crowded conditions) it still remains manageable. Some Eriocaulon spp. also have a similar look, though they don't do well in every condition.

 

[midnightbast]

Consider Eleocharis montevidensis for a straight-growing background grass. Differentiating between E. montevidensis and E. vivipara can be tricky due to varied visuals. E. vivipara might show wiry growth with seed heads, unlike the clean appearance of E. montevidensis. Routine tank maintenance may involve trimming without branching or browning concerns. However, V. nana, while appealing, might require effort to control runners based on your experience with common vals.

 

[DennisC]

I'm going to use E. Montevidensis but have no experience with it. Looking at sources, some show one clump per pot, others 2 or 3. What's the recommended spacing for planting clumps? Are the clumps I see single plants or divide-able?

 

[Allwissend]

usually you can divide it like with any Eleocharis species. Usually when you open the rockwool in the pot you will see one or more strands with roots and leaves along them. Just plant them along the area oyou want or plant the clump 10 cm apart and let it fill in.