4 cats one bed room appartment THUNDER DOME!!!!!

Question
Hello my name is Josh and I live with my girlfriend in a one bedroom appartment. We have four cats three females and one male. Chunks (male) has a sister Gui (female) we also have two other cats Stella (female) and Jazz (female) they are sisters.    
Here is our problem #1, Chunks is very aggressive twards Gui  it's like he is trying to mount her, and she screams and just hates it,Some times Chunks will sit outside of where the litter box is and Gui is stuck in it for awhile. Problem #2, Stella also picks on Gui, so we usually find Gui behind something like the couch and so forth. It's like Chunks and Stella have it out for Gui. Problem #3 Gui hates being separated from Chunks, if you put one in a room the other will sit infront of the door till the other comes out vice versa. It's like the cats are tence all the time, it's like they can't relax they are always on edge. So we bought this thing that looks like a glade plug in, it's to help mellow them out and stuff. But it does not seem to work though. Oh on another note Jazz is cool with everyone. Please help us we love our cats and hate seing them like this, and we don't want to get rid of them so that is not an option. The cats have lived together for 2 1/5 years now and its better but not. It's like this we got Gui and Chunks first then we brought in Stella and Jazz. Stella and Gui it seems to me that they are always fighting for alpha female or something when will the madness stop. Please we need help, we need all the cats to just mellow out. I feel bad because Gui is always slinking around and it's like she cant relax or something. Please help us send me an email @ akidnamedkirk@hotmail.com I will check it daily  

Answer
Hi Josh,

I need some more info so I can help you. Are all your cats fixed?  How long ago did you bring all the cats together? Is this new behavior? Have they always been fighting? Who is the main instigator?What has changed in your household? What are their ages? Do they eat together? Sleep together? Get back to me with the answers and any thing else you can think of. I need a more complete picture. With this many cats it helps to know everything. I'll be able to help you then . Good luck.

Ciao, Karen