Hello,I have gotten these from work.Could they be converted so i could use them over a reef tank.Could i buy a reef led module and just swap them over?
I probably wouldn't go with a single color chip like the one you linked. That one is just basically blue with no other colors. I would search for a 20,000K - 30,000K chip to get more colors, although the color accuracy really depends on how honest the COB manufacturer is when classifying the chips. Something like this perhaps. You'll just need to make sure the voltage and current for the chip will work with the power supply.
I also wouldn't use this without a PAR or lux meter to measure intensity. With a DIY LED that's not really made for hobby use, there's not really any telling how intense it could be.
I've wanted to experiment with COB LED chips for a while. Their simple construction and cheap price would make for a great reef light if you can get the right spectrum. Keep us updated on this.