The most important factors for growth in any cichlid, are water changes.
In nature these species are in 100% water changes every day, all day..... so
Water changes reduce the build up of growth inhibitors like hormones and nitrate.
If you do one 50% water change every 2 weeks, it will grow slower than if you do one 50% water change every week,
or it will grow faster if you do two 50% water changes per week etc etc..
This is why many breeders that want to get their fish to market faster, will do a 50% water change every day.
Below is a shot taken where I catch Andinoacara coerleopunctatus, close cousin to GTs
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As you can see by the current in the river where I catch them below, they are not sitting in any hormone or nitrate concentrations very long.
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