Can You Have Too Much Light

[Meaty24]

I have a 185 gallon tank with three (3) 400 watt metal halides and 2 T-5 itinics. I set up the tank almost 1.5 years ago and have almost no coraline alge.

Can my lights be too powerful? Are there negatives of having as much power as I have (other than a ridicilous electric bill).

[sassafrass]

I would venture to guess it more to do with water parameters than lighting , in the areas under my MH's no coraline grows however in the more shaded areas it proliferates. What are your parameters?

[Meaty24]

Everything is in range, except by nitrates are around 40-50 and my Alk is about 14. I have NEVER been able to bring down my Alk. The calcium is 425. I know, weird.

[sassafrass]

What is your PH and Mag ? Do you run a refugium?

[Meaty24]

Ph is 8.3 and Mg is 1250 (i just added mg tonight to raise it)

[Meaty24]

No refug.

[jeffreyliu838]

IMO, you have way too much lighting, but I don't really know the whole story... How deep is your tank?

EDIT: Reflectors would make a difference, too.

[sassafrass]

I am not enough of a water chemistry expert to tell you why your alk is so high , I would guess that has something to do with your lack of coraline growth .You might have better luck on the water chemistry forum.

[Gdevine]

Go ask Grim in the lighting forum...he'll help you. Look for his T5 Q&A thread.

[anememoni]

This guy has 2040w on a 225 and coraline grows just fine. http://www.reefcorner.com/225_gal.htm

[iamwrasseman]

thats a lot of light ,wow .he doesnt have them all on but for a few hours he ramps it up then dimms it down .4-400 watt MH wow sunglasses any one ?

[Moondog123]

yes

[dbreef]

i would go 30k on the halides and 10k on the t5's may help bring down phosphates or hidden NO4's contributing to nitrates i run a single 150 de 30k and get excellent growth and exstention i need to change my pc's to 10k from the acintic's i havein but am in no hurry as i love the blue look of a bright light colored blue reef over a yellowish 10k look my fish do awesome also they are growing alarmingly and my carpet anennome is lookin awesome too!!

[sassafrass]

<a href=showthread.php?s=&postid=14195834#post14195834 target=_blank>Originally posted</a> by dbreef
i would go 30k on the halides and 10k on the t5's may help bring down phosphates or hidden NO4's contributing to nitrates i run a single 150 de 30k and get excellent growth and exstention i need to change my pc's to 10k from the acintic's i havein but am in no hurry as i love the blue look of a bright light colored blue reef over a yellowish 10k look my fish do awesome also they are growing alarmingly and my carpet anennome is lookin awesome too!!
What does that have to do with this thread?