Freshwater inverts and fish recomendations

hey i am new. sorry if this is in a wrong section but here it goes. i am a begginer fish tank owner. all i got are a couple of plants, 2 freshwater angels (my third one died), one otocinclus catfish (the other died) and a frog. does anyone have any recomendations on what types of fish or inverts i can put in their? (did i mention it was a freshwater tank?) i am thinking about a freshwater clam but i am not sure about anything else.

 

How long was your tank set up before you introduced everything? Do you test your water parameters? May want to find out what caused the deaths before you introduce something new.

 

Also what size tank?

 

I remember my first aquarium, it was 29g freshwater, I miss those red tail sharks... Snails are fun and they reproduce a-sexualy.

 

my tank was setup for a couple of weeks before i got the critters. its a 29 gallon. the one angelfish died because of high nitrite levels but i fixed that. not sure how the catfish died. all i knew was he had a red spot near his mouth.