One of the good things in changing tank is u hv d opportunity to re-do your rock arrangement. In my previuos tank, My gbta which was purchased April last year, decided to stay in a place with very little illumination, thus it suffered from bleaching but still surviving after almost a year,
Now, i positioned the rock in such a way that it would get enough light, luckily it did not move and hoping will stay there permanenty as it did in d past months and gain back d color. Hoping also that the pair perc, whic were purchased together w gbta, will notice it and decide to hv d gbta host them.