Hi Sarah.
Why not tell ipus a bit about you and your fish?
Here's a little about me:
I keep neon tetras and bristlenose catfish. I live in regional Victoria Australia and I like cryptocerns ( one of the only plants that dont die in my tank lol )
I have a 125l tank planted. I have a variety of fish- glass cat fish, balloon mollies, a Plecoptera, an elephant nose, dwarf gourami, neon tetras, sword tails, catfish, bumblebee goby, a shrimp and some stripy worm type things. The elephant nose is the lates addition and I have only just realised how hard it is going to be keeping him alive!!
I live in England
Plecoptera- lol that's an insect- sorry predictive text!
Common plecos grow to about a foot in size so you might want to think about rehoming yours, plus the elephant nose won't be too far behind it.
Can you be specific with regards to numbers of each species as it sounds like your overstocked. As a rule you should have around 33 inches of fully grown fish in your tank.
I will consider re-home or tank upgrade when the time comes. I would never be cruel to them.
I know sounds lot of fish but am pretty sure not over stocked. They have loads of room to swim and get away from each other, loads of hiding places and plants to sit in.
3 neon
3 dwarf gourami
2 balloon Molly
3 sword tail
2 bumblebee
2 worm things
3 glass cat fish
1 tiny cat fish
1 pleco
1 elephant nose
Ok, I think you're at about maximum based on that although I'd rehome the unsuitable fish before they become an issue. You don't want them to get stunted and stressed.
However you also have low numbers of shoaling fish, neons and corys (catfish) should be in shoals of 5 or more. I think the glass catfish are the same too.
If I were you I'd rehome the Plec, elephant nose and maybe 2-3 of the other types to allow you to up the shoals of what you decide to keep. I'd also find out what the "worm things" are in case they're not suitable. Got a picture or can you describe them a bit more?
I don't plant food as all my plants are indestructible ( had to go through about 200 before I found the right ones ).
Personally I dont think that its worth all that fuss with the right dosing for plants that are similar to ones which don't need plant food.
Most don't agree so it's all up to you. I don't think they hurt fish if dosed right. Could be wrong though as I've never used them.