SPS lighting question

[richierich2000]

I have a 210g that is 72x24x29.5 I was running 250w se 14k bulbs and LB mini's I do not think I had enough light for a 29.5" deep tank. so I went to 3 400w 12k bulbs and still the mini's going to add 36 3w leds total 6 on each side of the 400w

my question

I read somewhere that sps only need so much high light then after that you are wasting light. if that is true I should be able to run my 400w for like 4-5 hours and the leds of 10 hours.. right?

 

[dzhuo]

You are referring to a phenomena called photoinhibition. Photoinhibition has nothing to do with the length of light exposure but has everything to do with intensity. In other word, if lighting intensity excesses the coral's ability to photosynthetic, it happens almost immediately. If the intensity isn't strong enough, it will never happen regardless how long you expose the coral to the light (but you might stress the corals in other ways). Your proposed lighting scheme seems reasonable. I would run the MH for ~5 hours (when you are at home) and the LED 8 to 10 depends on your liking.

 

[ColaAddict]

I have a 30 inch high tank and only use 250 MH. Of course I only keep the SPS on upper half of tank. Unless you have SPS in the bottom of tank, I don't think you need to use 400watt MH, I think it's just a big waste of energy/money.

 

[SaltwaterAdict]

You are referring to a phenomena called photoinhibition. Photoinhibition has nothing to do with the length of light exposure but has everything to do with intensity. In other word, if lighting intensity excesses the coral's ability to photosynthetic, it happens almost immediately. If the intensity isn't strong enough, it will never happen regardless how long you expose the coral to the light (but you might stress the corals in other ways). Your proposed lighting scheme seems reasonable. I would run the MH for ~5 hours (when you are at home) and the LED 8 to 10 depends on your liking.

Not to side track the thread but was wonder what would you suggest for 250's using lumenarcs minis as well on 180g mounted 8-9in from water surface to bulb?

 

[dzhuo]

Not to side track the thread but was wonder what would you suggest for 250's using lumenarcs minis as well on 180g mounted 8-9in from water surface to bulb?

You mean bulb selection?

 

[SaltwaterAdict]

You mean bulb selection?

No amount of hours lights on for sps corals like the OP's wondering. thanks

 

[dzhuo]

It would just run the MH anywhere from 5 to 7 hours. However, it's very well known that calcification runs much higher when there are sufficient light - a process generally referred to as “light-enhanced calcification” - which normally means faster grow rate. Certain corals are known to grow as much as 4 times faster during the day vs. at night while others have recorded up to 90% of the grow happens during the day. I personally run 6 hours and am happy with grow.

 

[richierich2000]

ok so my plan sounds like it will work. my par at the top went from 350(250 w/old bulbs) to over 1000(400 used bulbs going to put new one in after corals adj.) my meter only goes up to 1000.

the way my tank is set up most of my coral are 6-10" from bottom so that might be why I need more light

going to have my led stuff this week