Just let us read what Arend van den Nieuwenhuizen wrote about a place in nature where he found Puntius ( Barbus ) titteya in Datz 2000/ 9 pag. 16 (I translate, this time from German to Englishl) ................

The sherry-barbs - or "Kopperbarbs" only live on the ile of Sri Lanka, in well shaded and for the most slow streaming brooks and rivers.In general the soil in waters in wich they live is sandey,slightly bemired and often couvered with a thik layer of fallen leaves. On single findingplaces Cherry-barb-sites Cryptocorine occur and on many places they form extended fields along the banks. We would have been verey surprised finding Cherry-Barbs during the rainy season in such a brook with turbulnt water like this.But also in the drie season the water under the leaves of the tight stocks of Cryptocorines may flow very fast, without one notices. Until here the quotation..... It seems as if the citation has inspirated Reulen. Given the date that of course is inpossible.
My suggestions for supplementary population:
At the surface Aplocheilus ( lineatus ) dayi, Black Ruby barbs ( Barbus nigrofascistus ) but it have to be the right old fashioned well develloped ones and purple like coal. But be ware that you don't overpopulate the aquarium !