# Too much light?



## fish_fasinated (Mar 30, 2006)

Is there such a thing? I just set up a 65 (36x18x24) with dual 150W MH. not sure how its going to go. what is the most light you've ever put over a freshwater tank?


----------



## Sharkfood (May 2, 2010)

That's an ungodly amount of light IMO.

I run 2x39W T5HO on the same tank and have never had an issue with lighting being too low.

I'd suspend those lights several feet over the tank so you don't boil the fish. I grow eggplants and peppers under about 2/3 of that light.


----------



## Darkblade48 (Jan 4, 2008)

I agree with Sharkfood; that is too much light for your aquarium. Unlike saltwater reef aquariums, planted aquariums do not need that much light.

If you use that much light, you will have algae problems for sure.


----------



## Hoppy (Dec 24, 2005)

I keep waiting for someone to report that they use a one megawatt laser to light their 10 gallon tank....and everything looks great:hihi:


----------



## Master Se7eN (Aug 23, 2010)

I am useing a 1 meggawatt Laser to light my 10 gal tank and have never had any algae problems... Just sayin...


----------



## Master Se7eN (Aug 23, 2010)

Actually I have a 55 gal tank and am useing 2 54 watt T5HO bulbs, one 10,000 k and one "grow" they are both about 6 inches above the top of the tank. I use DIY CO2, and can't currently get ahold of a decent price Pressure set up. (I have 10 2 liter bottles going, 2 changed per week) I have very little agae , but have my lights on a timer and moniter feedings.


----------



## rwong2k (Dec 24, 2004)

i've done something similar before with 2x 150 watt MH,

my plants grew quite well and i didn't have any algae problems

but i've go away from that path a while ago and my tanks are all medium lighting now (approx 2 watts/gallon T5's instead)


----------



## ibanezfrelon (May 23, 2010)

I've had 80w over a 12gal tank with diy co2 and not a single algae:tongue:






..the tank was in use only a few weeks before it was sold though:hihi::hihi:


----------



## MaStErFiShKeEps (Dec 6, 2010)

I have a 6500k 18w over a 2.5gallon tank, and no algae.


----------



## fish_fasinated (Mar 30, 2006)

currently i'm slowly staging the lights in and keeping my old 20g with 54W 2xt5HO going as a reserve tank in case things go bad. currently one light runs 6 hours and the second comes on for 2 hours for a mid day burst. temps haven't changed much, 1-2 degrees if that. its a bit of an experiment, as i don't have the space for 100+. i'm going to bump both lights up to 8 and 4 hours soon, continually monitoring the temps. i'm prepared to sell these off and purchase a 6 bulb t5 fixture if its not going to work. once i'm in a house this tank gets converted to a reef tank. lol


----------



## fishykid1 (Apr 5, 2010)

People get a misconception when they use the WPG rule. The WPG rule is grossly outdated.

Not all t5 lamps put out the same amount of light. (lumens) And besides that 300W MH over a 65 is getting into reef lighting territory, IMO.

I'm now running 1 bulb of 24W t5ho on my 20G and I'm still able to grow pretty much any plant I could possibly want.

On my 75G I'm going to run 3-4X54 t5ho and I should have plenty of light to grow most any plants. Besides that, 4 t5's will put a ton less heat out than MH.


----------



## mmelnick (Mar 5, 2010)

That should be fine if you're prepared to inject tons of CO2 and keep up with your ferts to allow the plants to actually use taht light.

If not you'll have yourself a nice 65 gallon algae farm.

The thing is you'll notice any changes a lot faster than you would if you were using a quarter of that light. So just be prepared for a lot more maintainance.


----------



## fish_fasinated (Mar 30, 2006)

sure am, its why im slowley increasing the times. i havent started fertilizing yet but am starting a dosing routine when i decide to increase the time period. really experiment with timing and stuff. but take my time with increases.


----------



## fish_fasinated (Mar 30, 2006)

I'll post pics in the appropriate area when its stalked better. mentioning the stalk and plans


----------



## redfishsc (Aug 29, 2010)

If you were using 70w halides, I'd call it a med-high light tank. And it would look quite nice. 

150s are a bit much on a tank that size but as long as you don't mind the excess energy consumption, give it a shot.


----------



## feral13 (Jan 17, 2006)

Im running 2 150w MH on a 75g.

I am fighting an odd brown hair algae that supposedly flourishes in low light according to what I can find. Some say its also caused by excess Iron (which I find easier to agree with). My lights hang about 14" over the tank.

I have a small amount of green spot algae, but any less would make me paranoid. I have had algae in every tank I have ever had in my life (30+ years). It should be there. Its supposed to be there. If someone says its not, I think they are lying or their water is toxic (and it should still be there if its toxic).

Back to the Halides...

I came very close to getting 70w fixtures. If I had it to do again, I would have gone with my gut and bought them instead of the 150s.


----------



## Sharkfood (May 2, 2010)

Brown hair algae will grow in high or lower light. I've kind of come to the conclusion it's an inevitable part of change. I see it show up sometimes when a tank is new, or the gravel gets torn up in a rescape. Curiously I've only ever seen it on my glass, much like GDA, but even uglier. Usually it goes away as quick as it shows up.

There's always going to be some miniscule amount of algae, or spores at least, but it shouldn't be on your plants, and it shouldn't really be noticeable without looking for it (unless you're growing it on purpose for some weird reason). I always figure if I have to actually clean it off something, or magfloat the glass more than once every month or two, then it's an algae problem.


----------

