6500k caused corals to turn brown?

[jonathan543]

hi currently using 4x65000k t5 tubes for my 2x1.5x2ft tank. used to have 4x20000k tubes but the corals wasn't opening up nicely. so after changing to 65000k tubes, there was a very pleasant noticable change to my corals. the zoos had opened up & minute colours started to come out and the rest of them had seemed to opened up & grew in size. however, once i bought a pulsating xenia from a fellow reefer, it was white with dark brown polyps. it extended pretty well but as time goes by, it started to turn brown liao. now, it had turned completely brown with the polyps in a darker shade colour! and once bought a blue tip white goniopora & again it turned into a blue tip brown goniopora!

so wad happened here? should i change to 10000k tubes instead? but other corals are pretty healthy though my nutrient levels are damn high heheh...

[blueheaven]

If you have problems relating to coral fluorescence, then the 6500k tubes might be the cause.

This is because the fluorescent proteins in corals are expressed by wavelengths in the blue spectrum. The 6500k tubes produce light that is nearer to the red spectrum than the blue spectrum and thus might make some corals look brown

[jonathan543]

hi blue heaven... yup 65000k tubes do make most of the red zoos & gonioporas look more brown than red... but wad i really meant is both the white goniopora & xenia turned brown in juz a couple of weeks! they are white for the 1st few days before slowly & surely turning brown completely! ever seen how a blue tip white goniopora turned slowly into a blue tip brown goniopora looks like? hiaz... hearbreaking man... the white used to be so eye catching... now looks like brown xenia at a glance but both healthy lei... juz the colours haiyo... any solutions bro? change to 10000k tubes would rectify the problem?

[blueheaven]

The change to a 6500k tube might spark off an increase in zooxathellae number and this turns your corals brown.

White corals are very very likely to be bleached and much as they look pleasing to the eye, they are in very bad health. But if you are able to nurse a bleached coral back to health, you have done a greater good

[jonathan543]

hahaa... cool!