My New Molly Is Aggressive Toward My Pleco?

I just got a new lyretail molly and added her to my tank tonight. She has been nipping at both of my albino bristlenose plecos.

The fish in my tank are:
6 guppies (4 female 2 male)
1 powder blue dwarf gourami (male)
2 orange panda mollies (1 male 1 female)
1 Dalmatian molly (male)
1 lyretail molly (female)
4 black skirt tetra (all female)
2 albino bristlenose pleco (female I think)

The lyretail doesn’t seem to bother any of the fish other than the two plecos and has tried to nip at them several times. Is this something I should be concerned about or is it just because of the new environment?

 

What is the tank size? You should have at least 50 gallons for all those fish imo

 

It’s a 20 gallon tank but all the fish are pretty small and (as far as I’ve been told) aren’t supposed to get too much bigger. I’ve had the tank set up for a couple weeks is all so I’m still very new to all of it.

 

It’s a 20 gallon tank but all the fish are pretty small and (as far as I’ve been told) aren’t supposed to get too much bigger. I’ve had the tank set up for a couple weeks is all so I’m still very new to all of it.

I suggest you read about the nitrogen cycle before reading any of the things after this sentence

2 bn plecos will produce a lot of waste and might fight so 20-25 gallons is recommended for each bn. You also have a lot of livebearers which also have a large bioload. Even by the inch per gallon rule that tank is overstocked. The plecos will get 4 inches, molly will get 3-4 inches, guppy 1 inch, tetra 2 inch and dg 3 inches. Also those livebearers will breed very fast and quickly overstock your tank even more

 

Agreed If you weren't so overstocked I would suggest more friends for the molly, unless she can start schooling with the other colored ones. Be changing water often, dosing with safestart, and changing filters often. May have to rehome some unfortunately

 

Thanks guys! Sounds like I just need to look into rehoming some fish or getting a bigger tank!

 

I vote for a bigger tank.