Looking at your sig there I noticed what is going to happen if that's the tank you are posting about. Watch for signs of aggression. There's a ton of fish in there and fish that should not be housed together. You are bound for murder sprees as they get bigger and mature. A 29 gallon is not big enough for those fish at all. You are headed for a disaster.
I don't mean to sound mean. I'm just being honest. African cichlids, with few exceptions of small dwarf species and shell dwellers, should never be housed with South American fish and need at least a 75 gallon tank.
How long has the tank been up and running with fish in it?
The bio looks like it's in the beginning stages of establishing a nitrogen cycle. Whether it is or not....with that many fish in there...the bio is headed for a breakdown unless you do some serious changes...not just water either, but the tank overall...it's population.
I suggest you start doing 10% water changes up to two times a week. Suppliment bacteria with Cycle or Nitromax. I have my doubts about the safety of Bio Spira in certain situations such as yours. Bio Spira should, IMO
, be used as a cycling agent and not as a remedy for bio distruptions. Get some zeolite and put it in the filter to help with the ammonia and use Prime or Amquel Plus water conditioners to help protect the fish from nitrite and nitrate poisoning.
Clean the filter but rinse bio material in used tank water (not tap). Change how you feed. Space feeds apart instead of one big feed in a day. Offer about three to four minutes worth of food divided into two or more feeds. Plan a day or two to give only half their original amount until water quality improves.
As for the South American fish, they are not compatible with either water requirements or aggression with African Cichlids. The hard water can hurt them in the long run. South American fish need soft water. pH between 6.5 and 7.0. Once in a while I'll come across a tank with plecos doing ok in an African tank, but this is far and few between and only with the more hardier aggressive species like the common pleco (aka trinidad). Gold Nuggets are not one of them. They are sensitive.
For those of you reading and want to know why I have my doubts about Bio Spira being used as a remedy....here's my explanation....
Bio Spira is live bacteria. When used as a remedy it is exposed to immediate ammonia levels. This can cause enough to die and create a higher ammonia spike. Even as a cycling agent, it can still produce ammonia due to the nature of the bacteria if not dosed correctly for the immediate population of the tank it's suppose to cycle overnight for...especially if overdosed.
When nitrifying bacteria populate in an environment, they will over populate themselves and start to die, producing ammonia until a balance is met between waste in the system they need to feed on and the population of the bacteria.
So what are you gonna do??? New tank in the very near future???....
Again, sorry, but why find yourself disappointed after things go haywire??? Might as well be warned now. Good luck...and I really mean that.