old lights = algae?

heres my tank set up before i ask my question: 90 gallon tank with 20 gallon sump, reef octopus 110 skimmer with 6 VHO T12 lights.

tank is 15 months old water params are: Ph;8.2 Nitrate,Nitrite,Amm,Phos;0 calcium; 460 AK; 14.1 salinity/SG; 33/1.025/24 temp; 80-83

now my question is i have a little green hair algae on my live rock and on my back glass wall and occasionally get some algae with little bubbles on the end and some brown algae that grows on my sand bed in one area, my light bulbs need to be changed but i was waiting until i upgraded to a better light fixture in a couple months, they are over a year old so my question is could this be the reason i am seeing these algae problems since my water params seem good? and my next question is there anything i can do to control it until i get my new light set up? maybe turn the lights off less? they are currently on for 10 hours a day (night/day) i was thinking about cutting it down to 8 hours a day since i dont have much coral. (just a few zoas and some mushrooms.

any advice is appreciated thanks.

 

Lights should be changed every 6 months. They can cause algae problems when they are older since they no longer put out the intended spectrum of light. This could be the source of your problem. However, Your test may show 0 for nitrates and phosphates Because the algae is using them. Cyanobacteria, a slime like oxygen producing algae (could be the bubbles you mentioned) and gha thrive off nitrates and phosphates. Do you use ro/di water for top offs and changes? If you use tap water this is a possible source of these nutrients. Test the water you are using. What type of food are you using? This is another source of phosphates. Is it possible you are over feeding? If you use frozen foods are you rinsing it first? You can cut your light cycle down to 8-9 hours, however I think you would see better results with new bulbs. If you don't have a refuge, this is an excellent way to export additional nutrients as well. Good luck!

 

Yes, old lighting will cause algae issues. Just keep a new one on hand and swap it out once a month to give yourself an idea how much your other bulbs have lost.

 

I use ro/di water and feed once a day and rinse the frozen food off and dissolve in saltwater from tank then I use a tube cleaner to lift the food away from the water so none of the nasty water from the cube goes into my tank. I really think it could be the lights since there is not to much algae there for it to be a real issue with excess nutrients but that's just my guess. I have six bulbs it's kind of over kill right now since I just have fish and some zoa's I might buy two new bulbs and just use two bulbs to light the tank until I get a new light fixture I sure would hate to spend 120$ on bulbs that I won't use in few months.

 

not sure if its already been said, but DONT CHANGE YOUR LIGHTS ALL AT ONCE...

if you change all six of those bulbs and dont bring your photoperiod down then you will 100% bleach your corals..

change one bulb a week, or change all of them and run your lights for 4 hours and each week go up a hour or so...or raise your fixture...

and yes your bulbs are prolly your culprit...could be rodi filters and food..