[Michael Hoaster]

It's totally up to you on both the sloping thing and order of introduction, redlobstor. But of course I'll give you my opinion…

The sloping of substrate suggests you would put the shoal grass in front. I think it would be better to spread it throughout the sand bed, thus preparing all of it for the turtle grass. No need to go shallower on the sandbed, unless you're trying to save money on sand. It's probably ideal to add the shoal grass first, as in nature, but I added all my grasses at the same time. I have no idea how long you would wait to plant turtle grass. As you may be finding out, there's not a lot of info available on seagrass aquariums. Have you checked out the "Old Helpful Posts" at the top of this forum? It's a goldmine!

Great questions. With that kind of thinking, I have no doubt you will succeed!