grass only tank


New member
Has any one done a Turtle grass only tank?
I am thinking on converting my 55 brackish tank into a SW but curious on turning it into a Grass only tank with a few live rocks in there.
I would like to place in there, Turtle, shoal and manatee grasses. I think this might be really neat with Sea horses and Pipe fish.
But like plant tanks, would I need to do anything to the substrate or just use regular sand?

Greetings All !

There's an aquatic biologist named Tom Barr (aka Plantbrain) who frequents this forum. He has some serious expertise in this area, and hopefully he will chime in at some point ...

Substrate type and depth is indeed critical in the cultivation of "seagrasses." These are true flowering plants (angiospermae) that we're talking about here. They have roots and require appropriate substrate. They will develop extensive roots systems and expand into new space via runners. I have found that "muds" (oolithic live sands) suit them very well, whereas more coarse substrates can be problematic.

Also, be sure of the species you are growing. Some seagrass species' leaves can reach 1 meter in length.

The seahorse / pipefish concept sounds really cool.

Attached is a "seagrass tank" pic I discovered awhile ago ...

Fine sands and mud substrates are best. For sand beds, they should be nice old organic rich DSB's for the best results. In newer beds, I have had luck by supplementing the substrate with plant fertilizer tablets. I've also seen some excellent results from people using fresh collected salt marsh mud mixed in the substrate.
Does turtle grass have deep running roots? I wonder if this could be a good way of de-nutrifying old used up DSB's?
I also have considered a seagrass dominated tank.

That picture posted by GDW is awesome and shows that a grass tank can be anything but boring!
IS there a sea grass that stays short?

I would like to do a JBJ NanoCube with grass (10 gallons).
Some real good info in the Fenner & Calfo book. I know most people bash on the Miracle Mud stuff but, I have used the fresh water version w/ some really awesome results. Some kind of "mud" of any brand might work. If I was going to try this I would probably mira mud. Now everyone can laugh @ me.
Seagrasses of the US Southeasten seaboard. Of these, turtlegrass (Thallasia) and widgeongrass (Ruppia) are occasionally seen for sale in the hobby.

IS there a sea grass that stays short?
Ruppia, Halodule, Halophila.

Try BillsReef (website) for Ruppia and Thallasia. IA sometimes carries Thallasia, and sometimes carries "rooting" algaes like shaving brush that are associated with seagrass beds.

Tom Barr's Fl Keys field trip might be a good opportunity to collect plants associated with seagrass communities.