I know that I am not an expert, but. I have only had mine for two weeks, but did alot of reading before purchasing and asked alot of questions.
If you are going for a beta again.(the info is for a betta)
You should not use anything that is sharp, this can cause cuts and infection, this also refers to plastic plants. So the shells, you may want to rethink, make sure that they are not sharp and that they are fully cleaned. I am from Florida originally and used to collect shells and know that some of them are quite sharp and have alot of dirt and other things attached to them.
I have typical aquarium gravel in mine and a real plant that he swims in and out of and even falls asleep on.
The gravel is higher on top of the plant to keeep it weighed down, but much lower in other areas.
Since the plant is not a rhizome it can be planted right in the gravel and have not had any probles, it is even sending out new roots.
Got some good info on
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