[jsgates]

My tank is nearing a year old things have been going really well. I am even keeping some SPS corals without problems now! I currently have a 4 bulb T5 HO lighting rig under the canopy of my 80 ga. bowfront with an Icecap ballast. Nativevaman from this forum was very helpful in getting me up and running with lights, however; I know a LOT more now than I did this time last year and am ready to make some changes to my lighting. My current bulb config is as follows:

front to back.....420 nm,6500k,6500k.10000k

My tank is currently nice and bright and corals are doing well. I run 12 hours of lights per day and have been having issues with algae growth on the glass. I have cut back on feedings, but am thinking that the bright lighting may be a contributing factor. I also have a JBJ 12 Ga. Nanocube Deluxe. My green encrusting Montipora coral looked all ugly and browned out in my 80 ga., but under the more actinic lights of the nanocube, it actually is green! So, based on this, I'm wanting to go a little bit more "blue" with the lighting to bring out the colors of my corals better.

What bulbs would you guys recommend to basically give my tank more of blue tint, but without drastically changing my lighting intensity? Some people have recommended dropping both 6500 k bulbs in favor of actinics. My SPS corals are more vibrant under bluer lights, but I want to make sure I keep the lighting intense enough for the SPS. I am also assuming that water temps may cool down a little if I go more actinic. and less intense lighting may help out with algae growth? Thanks for any suggestions or input. I would prefer to replace on two bulbs if possible, but will replace more if need to get the lighting I am looking for.

[demonsquirt]

Sounds weak. Though not perfect divide you tank size by the amount of total watts for an average per gallon. SPS tanks need 5 or higher. In a mixed reef with proper coral placement you might be fine be with more watts you would have a wider coral placement ability.

[pogodzib]

Lets not get into the whole watts per gallon debate. Different type of lighting are more efficient than others and different corals have different needs. Also, lighting should be based upon corals and tank height rather than watts per gallon.

As for color, there are many, many different T5 HO bulbs available, each with their own pluses and minuses. Anytime you change your bulbs to a more blue bulb, you're going to loose some par. I wouldn't swap out both 6.5k bulbs for actinics. You'll go from one extreme to the other. You may want to consider replacing one of the 6.5k bulbs with a 10k bulb and see what you think. At a minimum, I'd keep at least two 10k bulbs. You won't want 1-10k & 3-actinics.

[jsgates]

ok, so swapping out 1 of the 6.5 bulbs for a 10 k bulb, will cost me a little intensity. Depending on which of the 6.5 bulbs I swap out, will I see a noticeable difference int the color of my tank lighting? Like I said, I'd like a little more of a blue light as it brings out the colors of my corals better. The SPS I have is placed high in the tank. I am more interested in LPS & soft corals.....and gorgonians.

[jsgates]

Thanks for the replies. Anybody else have any input on this? Suggestions appreciated.

[jimw369]

When in doubt....actinic, 10k actinic, 10k

Chances are your 10k isnt going to really be that anyway.

Your tank is sill gonna be bright. IMO a nicer crisper bright but you are going to get rid of some yellow you dont even notice now. SPS high in the tank anit gonna mind a bit.

[jsgates]

Thanks Jim! Think I'm gonna pick up another actinic bulb today. I can always swap them back if I need too. Tank does really have a noticeable yellow hue right now, just want it to be a little more blue. Thanks for the suggestion.

[wesley6610]

Originally Posted by pogodzib

Lets not get into the whole watts per gallon debate. Different type of lighting are more efficient than others and different corals have different needs. Also, lighting should be based upon corals and tank height rather than watts per gallon.

As for color, there are many, many different T5 HO bulbs available, each with their own pluses and minuses. Anytime you change your bulbs to a more blue bulb, you're going to loose some par. I wouldn't swap out both 6.5k bulbs for actinics. You'll go from one extreme to the other. You may want to consider replacing one of the 6.5k bulbs with a 10k bulb and see what you think. At a minimum, I'd keep at least two 10k bulbs. You won't want 1-10k & 3-actinics.

I concur, I found that the more Actinics I put in my fixture simply made it applealing to the eye and didn't do too much for my corals throughout the day. I have a 5 bulb T5 fixture with 2 10K's, 2 Actinics and 1 75/25 bulb. IMO, I have a good balance for my tank and have seen great growth for all my corals. With the exception on one piece of Goniopora, hmmm.....