Mangrove newbie

I just received my first mangrove seeds. My question is, how do I place them in the tank? I have a piece of Styrofoam with 5 holes for each. They are about half in and half out. Is this correct or should I have them like 90% in the water? There aren't any leaves and there is a small nub at the top that looks like where the stalk would be popping out.

I know nothing except these need to rid my nuisance algae, any help is appreciated as usual

 

how tall are they?

 

small, maybe about 6-8 inches.

 

Do you have substrate or mud?

 

Yes a DSB but if they touch the sand they are completely emerged by about 4 inches of water.

 

That should be good. they are going to grow anyway. I would do 75-25 with them touching the bed.

 

If they touch the bed they are completely submerged. That's cool?

 

not really. IMO use the Styrofoam and atleast have the roots in the water and as they grow then put them in the DSB.

 

I am pretty sure the growth tip needs to be above the water

 

Ok cool. Thanks guys! ++