Lights Out Max Frequency and Duration

[_Mackus_]

I've been fighting what I believe his hair algae for quite some time. My former SPS tank is now, sadly and not intentionally, a FOWLR tank. It's a pretty aggressive algae outbreak, my tanks looks pretty bad, not just some light covering on the rocks, it's everywhere and its growing.

I've done 3-day lights out once every month or two, they make a little impact but the algae comes right back. I'm thinking that 3 days / once-a-month guidelines for lights out is the longest that coral can survive. Which I don't have any longer. So can I do longer lights out periods - or just do them more frequently, like every other week - without harming my fish?

Alternatively, could I move my fish to a temporary/quarantine tank and go complete lights out in my display? Would long lights out period be awful for my cleanup crew or biological filtration? If I can do that, how long would it take to kill off all the algae.

Thanks for any advice...




Tank and story details below:

I've got a 125 gal tank that's been running over 6 years now. Very shallow sand bed. I'm using GFO and carbon reactors, I've added an algae turf scrubber, I've shortened my photoperiod to 8 hours of T5 and no MH, I've cut back feeding as much as I think is reasonable. I try to change about 15 gallons of water a week, but I usually fall short and only change 5 or 10 gallons.

Latest chemical readings are:
Salinity 1.025
Alkalinity 7.0 dkH
Calcium 420 ppm
Magnesium 1080 ppm
Phosphate 0 ppm
Nitrate 10 ppm
Nitrite 0 ppm
Ammonia 0 ppm

I use a refractometer to test for salinity, Red Sea titration kit for Alk/Cal/Mag, Hanna ULR for phosphate.

I have a RODI unit for water filtration. I do a pretty good job with keeping up with filter changes, and two different TDS meters (one in-line, one handheld) both are reading 0 ppm.

I've got the BRS pukani rock in my tank. I know that can leech phosphate, but I followed the suggested steps before putting it in my tank. I set it up in a separate tank (well, bins) for months to leech out somewhere other than my tank. I used Sea Klear phosphate remover and checked that the phosphate levels stopped rising for over a month before adding it to the tank. Plus, the rock was in my tank for years before I had any algae issues.

[outy]

Me? I would do a 100% water change, 10ppm nitrate is ridiculous, and either use a fuge or cut back more on feeding. Your current program is not cutting it. Maybe a better skimmer.

Cutting back on light is the wrong work around.

http://reefcentral.com/forums/showthread.php?t=2655497

read through that, maybe a great idea in your shoes to cut back the GHA, but I would still do a 100% water change.

[Ron Reefman]

Shortening your photo period is pointless. Coral and algae only do photosynthesis for a set period of time (in the 4 to 6 hour range) so you are not slowing anything down at 8 hours.

You obviously have some fairly serious issues here and should look at all kinds of solutions. I think bigger water changes will help. Manual removal can have huge effects on algae growth. It's been my experience that some algae really don't like being 'harvested' and don't grow back well if at all.

As for lights out... if you have enough actinic t5 bulbs (I use leds, so it 's easy) go all blue over the tank full time. Your corals use the blue spectrum to do photosynthesis and the algae use red. So the algae will die back and the coral will still polyp out, do photosynthesis and look good (especially if it fluoresces colors). I've run my tank for weeks on just blue and all the corals were fine when I went back to normal (for me) lighting.

[_Mackus_]

Thanks for the advice.

I know I need to do better with consistent water changes. I used to be very diligent but have fallen off. Will try to keep up with that, and do some big ones right away. I've only got 5 gallon buckets for water changes so it's a slow process.

I'll look into all blue lights. I currently am using two ATI Blue Plus, one ATI Aquablue, and one ATI Purple Plus. I don't currently have any coral.

I've done manual removal off of my smaller rocks a couple times. Removed the rocks, scraped away all the algae with a wire brush, rinsed in saltwater, then returned to the tank. That got the algae off temporarily, but it came back within a month or so. It's not feasible for me to get the majority of my rock out of the tank, there are 4 huge rock pieces that I jsut can't get out unless I basically tear everything down. I do try to siphon out as much as I can

[der_wille_zur_macht]

Since you now have no corals, there's really no reason to have lights at all. I would cut back to the smallest amount possible - maybe even a single T8 - and only run it for a couple hours when you're home in the evening or something like that.

Maximize your turf scrubber. Consider growing macro in a fuge. Manually remove as much as you can. You need to solve the nutrient problem AND destroy/remove the current colony of algae.

It sounds like you are doing a lot of the right things and sometimes this just turns into awaiting game.