18 cichlids in an 18 gallon tank, WOW, breeding is not a sign of happy fish, they will breed in pure crap as its there natural instincts for them to keep the species alive, the rule of thumb for malawis is the bigger the better
if were going to compare expertiese then I have been keeping fish since the age of 12 and i,m slightly, by a few years, older than you aberdeen, and the last 10 years has been NOTHING but lake malawi cichlids for me, *lost interest in everything else*. I SERIOUSLY would not suggest or even try to put hope into some bodies head, that they could keep a healthy stock of cichlids in a 10 gallon tank.
I know not everyone has the space or even finances for a larger tank, but 10 gallons would be cruel, un interesting, and I have to say, it wouldn't work for me and it most deffiniatly wont work for the human hybrid. the peramaters would fluctuate too much, the temprature would constantly rise and drop, without good filtration they would be swimming in there own waste. no, dont do it mate, get yourself a 3ft tank if nothing else, as even aberdeens salousi need a 50ish gallon tank to be truly happy. there are no hard fast rules, just common sence, and this is why folk always say, the bigger the better, theres more room for any possible mistakes we may make.