Can My Kribs Breed If The Male Is Smaller?

I have a female krib cichlid which is maybe 3 inches long maximum. I just bought a male for her and he’s smaller than her.

Can they still breed? She chases him away quite a bit but once and a while let’s him into her cave before chasing him away again. She also seems to be fighting with my other fish (a gourami in particular) more now that’s he’s here.

Just wondering what to expect. Pictures below.

 

The Kribs should be fine. The Gourami may get stressed out and become susceptible to disease. Might want to place in a different tank if it is frequent harassment.

 

What size tank are they in? When breeding kribs I like to use a male that is larger than the female, I have had smaller males breed but not often. I have had the female kill the younger male's more than once.

 

A 26 gallon

Also is this swelling and redness normal???? It just started a couple of days ago

 

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