the heater helps to a point- higher temps are supposed to help them breed and grow faster, but they also die faster. check how hot you’ve got it and decide if the shrimp really need it.
how long have you had the tank set up, in total and also pre-shrimp? did you let it cycle for a bit?
you say the parameters are ‘good’, but what are they? if you’re using the api water test kit, then you’re probably okay but you should still check the gh/kh to make sure there’s enough minerals in there for the shrimp (the plants use minerals too)
algae and biofilm are (obviously) good for them to eat, but it seems like they do well with a bit of variety once in a while too. feeding more also = breeding more. if there’s a LOT of algae, maybe consider a shorter time with the light on and feed them a bit more if you’re concerned with overfeeding.
also, what’s the size of your tank, and how many shrimp are in there (approximately)?
if your shrimp are new/especially young, you might need to wait a bit for them to grow and settle in before they start breeding. on the plus side, once they DO start breeding, they really just don’t stop!
shioncalfee 
the heater helps to a point- higher temps are supposed to help them breed and grow faster, but they also die faster. check how hot you’ve got it and decide if the shrimp really need it.
how long have you had the tank set up, in total and also pre-shrimp? did you let it cycle for a bit?
you say the parameters are ‘good’, but what are they? if you’re using the api water test kit, then you’re probably okay but you should still check the gh/kh to make sure there’s enough minerals in there for the shrimp (the plants use minerals too)
algae and biofilm are (obviously) good for them to eat, but it seems like they do well with a bit of variety once in a while too. feeding more also = breeding more. if there’s a LOT of algae, maybe consider a shorter time with the light on and feed them a bit more if you’re concerned with overfeeding.
also, what’s the size of your tank, and how many shrimp are in there (approximately)?
if your shrimp are new/especially young, you might need to wait a bit for them to grow and settle in before they start breeding. on the plus side, once they DO start breeding, they really just don’t stop!