too much cichild bullying

[sippingtowel]

greetings, for the past few months we've got a 55g tall with 2 adult yellow labs, and 2 juvenile convict cichlids. The problem is that 1 yellow lab is extremely aggressive on the other, so much so that the non-dominate one has no black and even their eyes are pale excluding the iris. I've done what I could in terms of cover, so much that it is an eyesore, even than the dom yellow lab seems hellbent on finding and chasing.

The convict cichilds is also the same scenario.

Once again the tank has the following: 2 adult yellow labs, 2 juvenile convict cichlids, 1 angelfish, 1 guppy(yup... and no one ever bothers it).

Not sure what to do, I've been reading I should actually be overstocking the tank, is that the best solution to solve this? Relocating to another tank isn't an option.
disclaimer - I myself aren't a huge fan of cichlids, I am trying my best to take care of them for someone else...

[limmer]

That is quite a mix of cichlids.  I am surprised no one has eaten the guppy.
You could put a divider in your tank like a eggcrate diffuser.
Sounds like the convict has eye cloud from being stressed.

[Jeff1192]

I agree with Limmer. I have no idea how the guppy hasn't been eaten. The only solution I see if another tank isn't an option is a divider. I have a 90 gallon that is all cichlids and over-stocking definitely works....but not an option for you with the mix you have now.

[limmer]

Auction this weekend.
You could get rid of everything and restock with matching livestock or booster your stock with a few more cichlids the same size.