I was hopeing I could get some advice,information links on applying the data Sanjays site provides to practical application.

The reason for this is Im trying to decide on a lighting upgrade and every time I think Im making the right decisions, I second guess my understanding of the data provided.

The reasons I want to upgrade is Im unhappy with the yellowish tinge the XMs seem to have, Im also not happy with the spread from the small DE reflectors in my pendant.

My current plan is to upgrade to lumenarc minis, icecap ballasts with 400w radium 12ks.

The two lamps Im comparing are a 250w XM10k (my current bulbs) to 400w Reeflux 12k.

The plots look similar except for a large spike from 440-460nm on the reeflux.  What is the significance of this to the tank inhabitants?

How do the numbers provided in the graphs relate to PAR?  Is the PPFD number PAR over the entire spectrum? Are the irridance numbers on the y axis also PAR for a specific wavelength?

When I hear people talk about 300-400 Par for high light corals. How would I know that the lights I get will achive that? and at what depth?

Im sorry for the million question post.   If thats too much to get into I understand.

Thanks!

sjames

It has been a while since I have studied Sanjay’s charts in depth and it will take a little research to give you in depth answers. It would help to know the dimensions of your tank. What pendent do you currently have? How high above the tank is the bottom of the pendent you have now?

The 250 watt XM 10K is one of the best growth bulbs in its range. Rising your existing pendent and changing to a higher K bulb like the XM 15K would be the easiest and least expensive way to make the changes you want. The reduction in light due to going to a higher K bulb and being higher from the water may be significant for the corals. Another way to do what you want might be to add some supplemental Actinic bulbs. 

The 440-460nm spike on the Reeflux bulb is what helps makes it a 12K as opposed to a 10K bulb.

Steve

240G mixed reef, 2-24g nanos, 2-12g nano 6g nano, designing/setting up an anenome propagation tank system.

Thanks for the reply Steve,

I currently have a 48" mh/t5 combo unit (Aquamedic), with 2 250w 10k bulbs and 2 actinics.

My tank is 48x24x24, the current unit is about 8" off the water.

Tank is bare bottom with minimal rockwork,  Highest rock is perhaps about 12" from the bottom.  Inhabitanta are mostly sps with a maxima clam on the bottom.

Yes I was worried about loseing too much par by moving to a higher K bulb in the same wattage.

An additional factor is glare becomes an issue if I raise the existing fixture too high, the tank is already pretty high.

But Im really only planning on keeping sps and clams.  The I4 would be a par downgrade from what im useing right now.

They compare it to a 250w XM20k, which looks to be a fairly low PAR bulb.

argi