So I'm still trying to put all the pieces together for this puzzle together! I'm looking at the Lunar Aqualight High Output T5 Fixtures ? Is that a good lighting for a 29 gal reef tank or its a little bit much ? Should I start with something different ? Please let me know! Thanks :fish1::fish1::fish1::dance:
I doubt you will find that 4 T5 HO bulbs over a 3 foot long tank will be too much light. And it might not be enough to keep corals that need a lot of light (like certain acropora species), though that will depend on where you place them in the tank.
I looked up the fixture you mentioned, and it's hard to discern whether the 30" long Coralife fixture has 24" long T5 HO lamps in it. Standard sizes for T5 HO lamps are 24", 36", 48", etc..., so I'm thinking that the 30" long Coralife fixture uses 4 24" T5 HO bulbs. Since each 24" T5 HO bulb is 24W, if you select this fixture you will be getting 3.3 watts/gallon.
Typically, that's on the low end of the watts per gallon rule of thumb, so it may be a bit weak for certain stony corals and photosynthetic clams. But it will certainly be enough for soft corals like zoanthids, palythoas, and mushrooms as well as low-light requirement stony corals.
Most highly successful stony coral tanks tend to run in the 6 watts per gallon range for fluorescent/metal halide lights. Note that this watts-per-gallon rule doesn't apply to LED fixtures. LEDs are more efficient, and 6 watts per gallon would be nuclear intensity that would likely fry corals and PS clams.
Speaking of LEDs, they've gotten cheap enough to where you've a decision to make. The fixture you're considering is $240 (assuming it's the 30" long one). You will need to replace the fluorescent bulbs once every 6-9 months, and 24" T5HOs cost about $20 each. For a 30 gallon tank, one of the Aqua Illumination hydra fixtures would be appropriate. They're $400 each, and you will need to add a controller and some sort of mounting solution to the total bill. However, you won't need to replace the LEDs in the way you must replace fluorescent or metal halide bulbs, so the cost of ownership is considerably lower. And an LED fixture like this includes timers, ramp up/ramp down intensity for sunrise/sunset and moonlight, plus the ability to alter the spectrum of the light over the tank at will.
Also, since a lot of the LED fixtures are modular, you could easily use the light on a bigger tank if you decide to upgrade in the future (you just need to purchase additional ones to cover the larger area). The example I gave is a high-quality, high-end fixture. You can also get Chinese-made, less functional but less expensive LED fixtures as well.
Finally, note that LED fixtures put out very little heat. T5HOs put out significant heat. If your tank is going to be located in a room that is continuously ACed to 75 deg F or less, and if the top of your tank is open, that heat output may be no big deal.
Note that I'm not trying to talk you into an LED fixture - T5HO fluorescents are a tried and true lighting method, and so are metal halides. But you may want to consider all of your options.
