Hello, currently I’m cycling a 20gal long to hold guppies or endlers not sure yet some shrimp,snails and possibly a bn pleco and I plan on doing a lot of guppie grass,floaters,Anubis and different types of moss but I’m unsure on what substrate I should pick should I do gravel or a nutrition substrate for the plants i also plan to mix in crushed coral to help raise the gh would that affect the plants? I’m also trying to do the substrate for around 30$ max. Suggestions?