葉子顏色偏淡帶紫色, 請問如何改善?

係屋企同公司都有種非洲紫羅蘭, 但發現新生既葉顏色都越來越淡, 仲見到紫紫地, 係光線或肥料不足嗎?
已經試過擺係唔同既地方, 但情況都係咁樣, 請各位指教一下~~

The plant is healthy. The back of the leaves should be red in colour. When passing through the greener leaf, it shows the purplish effect.

即係咁樣係屬於正常？因為初初種嘅時候，佢啲葉都好緑，大大下新生嗰啲葉就係青色，所以有啲擔心

可能太光

依家擺嗰個位，朝早會有一個鐘頭有啲較猛嘅陽光，咁我試下擺係暗少少地方啦，唔該曬