Is It Okay To Add These To 5G?

[plantbabby]

I have a 5g tank with a good-sized mystery snail, a ghost shrimp, 3 guppies (will possibly move the guppies to my larger tank), and 2 marimo balls.
 
They're supposed to be hardy plants, but will they negatively affect the health of the tank's current inhabitants?
 
-Dwarf hairgrass (Eleocharis parvula)
Is it okay for guppies? I know they're fine for snails and shrimps.
 
-Banana Plant (Nymphoides aquatica)
 
-Red Flame (Echinodorus red flame)
 
I splurged because they were on sale :')
 
EDIT: forgot to mention I have a small glass tea pot, a small conch, a tiny shell, a tiny piece of amethyst, and a teeny-tiny cuttle bone piece (for the snail) inside the tank as well.

 

[Munroco]

I don't see any reason not to plant them. Not sure if mystery snail eat plants or not.

 

[NickAu]

 
Not sure if mystery snail eat plants or not.

Mine dont, They are too well fed with good quality pellets  brine shrimp and blood worm to bother eating yucky old plants.

 

[SantaMonica]

Pics of the setup currently?

 

[Jeremy180]

 

 
Not sure if mystery snail eat plants or not.

Mine dont, They are too well fed with good quality pellets  brine shrimp and blood worm to bother eating yucky old plants.
 

LOL, Nick spoils his animals so much

Plant-wise you can add as much as will fit, but I wouldn't add any more animals to this tank, myself.
EDIT: I bought two bananna plants for my 29 gallon a couple months ago and will be returning the biggest one soon.
the underwater portion is about a foot tall and almost as wide, and it's sent a few pads to the top of an 18 inch tank, too.

 

[Ch4rlie]

Both your plants, Echinodorus red flame and Nymphoides aquatica grow pretty big and would soon be too big for a 5 gallon tank to be honest.
 
Plant very rarely have any negative impacts on a aqaurium and the inhabitants, its only when plants are non aquatic or treated with pesticides and suchlike that there may be issues, especially with shrimps and snails.
 
I heartily recommend to have suitable aquatic plants for any aquarium as this brings many benefits, not least helping with nutrients, ammonia, and nitrate whicch helps keep the water column stable and healthy for inhabitants, as well as making the tanks look good and more natural, of course this helps ease stress on fish to have shelter or hiding places available.
 
Though have to mention that 3 guppies will survive in a 5 gallon tank but that would be the very minimum size I would give for 3 of them, a Betta would be a more suitable choice for this tank size.