still fighting algae for months

I am beginning to think this problem is either due to the lighting or not enough water flow. I switched lights from dual actinic 420/460 130watt bulbs to two dual 6500/10000 daylight bulbs 130watt. I have not turned my MH bulbs on since the switch because they are old and need replacing. I do not have any coral left and am down to my last fish which is another reason I leave the MH off. All the parameters are at proper levels, I use RO/DI water. 210 gal. system w/ overflow and two powerheads. The water just has a yellow "tint" to it with the daylight bulbs and the algae has been overtaking the rock and sand ever since I switched the lights. I am considering purchasing another actinic 420/460 and using one of those with one of the daylight bulbs. Does this seem like the algae is due to the lights? Or just not enough water flow. I never had this problem until I started running the daylight bulbs. Any suggestions would be great!

 

I think that is your problem. Plants and algae grow very well when the light is in the 5100k to 6500k range. That is why a lot of us use bulbs in that range in our fuges (it causes macro-algae and Mangroves to grow like mad). You would be best served by running lights above the 10000k range as that will slow down the algae growth the higher up the Kelvin range you go.

 

6500K is an ‘OK’ spectrum to give your tank, in my opinion you want to stay at least at 10K or higher for a reef.. Most algae in the ocean grows near the surface in the 4000-5500K range. The deeper you go in the ocean the more the spectrum is filtered out and turns to mostly blue – or higher Kelvin (21000 K – blue).

You said your tank has a yellow tint, you could try running fresh carbon to see if its filtered out – more than likely will be. Aging light bulbs have decaying spectrums and could shine yellow also creating algae blooms.

Can you please post your full parameters, describe the tank and maintenance schedule?

 

I think it is just the lighting, the algae is worst on the rock that is near the surface. I didn't think the lights were cheap, they are CurrentUSA dual daylight 130W. I am going to get a new bulb and see if that helps. Thanks for the input!

 

Bulbs for sure...

 

Would you recommend getting rid of both bulbs and going back to only 420/460 actinics? Or do you think going one of each will be good? I hate to get rid of both bulbs because I just recently bought them. If I have to get rid of them I will...

 

The spectrum probably has something to do with it, but it could be your parameters as well. Even though you only have one fish, do you overfeed? Do you have a skimmer? Refugium?

 

Have a very large skimmer, only feed the fish once every week or two (has never been a problem feeding that schedule) refugium has cheato but I haven't been turning the light on in the fuge because I thought maybe it was causing some of the problem. Also run a marineland C-360 canister w/ bio balls/ceramic/carbon. RO/DI water, nitrates/phos./trite/ammon. all 0

 

I would say get rid of the 6500k no matter what. I know the pain, I have a brand new Current 6500k in the garage, just saving it for a planted tank. The 10k isn't the best IME but they are recommended for good coral growth. I run (3) 20k MH bulbs and 420/460 atnics with good results.

 

Sounds exactly like what I was thinking... I hate to eat the cost of the new bulbs because they were like 60 bucks a piece but on the other hand this algae is really frustrating me. I had a really great healthy tank going when I had my halides/actinics running. The other thing that makes me mad is I posted on here about which bulbs to get when replacing the 420/460 and I wanted to get the same bulbs (i LOVE the blue look) but someone one here convinced me that dual 6500k/10000k bulbs were "the way to go"... Thanks for the advice though, I really feel strongly that these bulbs are the culprit as the algae is not really getting better or worse, it's just surviving very well.