Filtration and mbuna stocking list for 75 gallon aquarium

Hello fish friends. I have a 75 gallon mixed mbuna tank with a fluval fx4 canister filter. It says the pump output is 700 gph which is around 9.3 x the filtration for my 75 gallon tank. This should be sufficient for an overstocked mbuna tank right? I have 14 fish in there currently, hoping to have around 18 or 20 total. Here is what I have stocked.
1 venustus cichlid, 1 cobalt zebra, 2 yellow labs, 1 yellow tail acei, 1 red tail shark, 1 kenyi cichlid, 1 auratus, 1 red top hongi, 1 albino zebra, 1 red zebra, 1 rusty cichlid, 1 pindani/socolofi, and 1 ob zebra. I know I don't have any groups but everyone seems to be doing great so far. I wanted as much color as possible. I have 12 big pieces of coral rock that provides plenty of escapes/hiding places for when they get to chasing each other. Does anyone on here have experience keeping this many different type of mbuna? Any tips would be greatly appreciated. Thanks!

 

Your FX4 is plenty of filtration for the 75 gal. It's not necessary to keep conspecific colonies of Mbuna. Solo males of various Mbuna species can coexist.
The Venustus isn't really the best choice for a 75 gal. tank or to be kept with Mbuna. They grow pretty big & will lose most of the battles with Mbuna, especially as a juvenile.

 

The filtration/bioload is not a big deal, but the space.
First of all: I would rehome the venustus as they get really big. I have regularly seen specimens of 20-25cm, also the red tail shark, that actually belongs in a bigger tank as well.

The mixing just to get as much colour as possible is longterm often causing problems. When there is only one female among them the males usually have a higher aggression level, also a female is not going to get old in such a tank. Every male of any species will try to mate and that either ends in her untimely death or hybrid fry that should either be culled or kept, but not given away. And as there are at least three hard-to-sex species in your list this is quite likely.
In that tank size I would estimate a species appropriate number of fish would be maybe 10-15 from 2 species in groups of 3-4 males and 4-6 females each. I could imagine a group each of the Iodotropheus sprengerae (rusties) and Maylandia lombardoi (kenyi). Keeping a colourful mix was practice in the 80s and 90s, nowerdays it's often considered bad fishkeeping.

12 pieces of coral rock... Can you please post a picture? If it's holey rock it may happen that fish trying to evade others get stuck in the rocks which can end fatal or at least with injuries.

 

The filtration/bioload is not a big deal, but the space.
First of all: I would rehome the venustus as they get really big. I have regularly seen specimens of 20-25cm, also the red tail shark, that actually belongs in a bigger tank as well.

The mixing just to get as much colour as possible is longterm often causing problems. When there is only one female among them the males usually have a higher aggression level, also a female is not going to get old in such a tank. Every male of any species will try to mate and that either ends in her untimely death or hybrid fry that should either be culled or kept, but not given away. And as there are at least three hard-to-sex species in your list this is quite likely.
In that tank size I would estimate a species appropriate number of fish would be maybe 10-15 from 2 species in groups of 3-4 males and 4-6 females each. I could imagine a group each of the Iodotropheus sprengerae (rusties) and Maylandia lombardoi (kenyi). Keeping a colourful mix was practice in the 80s and 90s, nowerdays it's often considered bad fishkeeping.

12 pieces of coral rock... Can you please post a picture? If it's holey rock it may happen that fish trying to evade others get stuck in the rocks which can end fatal or at least with injuries.

Its hard to tell if some are males or females. If I have a majority of males would that be better? If not. Which ones are best to group together? I know the venustus dosent belong with the mbuba. Ive read different things about the red tail shark though.

 

Red Tail Sharks & certain Botia Loaches can successfully coexist with African Cichlids.
Male Mbuna almost always develope egg spots on the analfin, while females only occassusually do, but usually don't.