Lighting configuration

Got my first electricity bill after turning on the MH for most of the month yesterday. Need to consider an alternative to sunrise +15 to sunset -15 for the MH.

TANK is 75 Gallon Acrylic 48x18x20

LIGHTING is Hamilton Retro - 2 x 250 MH 14K (electronic ballast)
- 2 x 39 Watt HO T5 Super Actinics

I currently have it set for:

Actinics - (sunrise) to (sunset +15)
MH1 (sunrise +15) to (sunset -30)
MH2 (sunrise +30) to (sunset -15)

NOTE: The Aquacontroller Jr. has a fixed limit on sunrise/sunset of 120 minutes for each. Using plus or minus, that would be a four hour window for sunrise and sunset ( 2 before and 2 after ).

Sunrise is currently 06:48 and Sunset is 5:34 which gives me:
~11 hrs Actinics
~10.5 hrs both MH
These times will get at least two hours longer during the summer months.

The tank is in the living room, so there will be light in the room from sunrise to sunset - no direct sunlight on the tank however.

I would like to NOT have both MH on at the same time and cut the number of hours to a fixed time per day, avoiding the afternoon hours between 2-6PM (I realize this is not possible). This is easy to program with the AquaController Jr., but I would like some advise about the times of day, duration, level of lighting.

My tank will be mixed with SPS/LPS/Zoaies/Ricordea. I will have small gardens of the Zoaies and Ricordea along the bottom and a column of LPS in the medium flow area (middle of tank) - with the largest part of the tank having SPS.

My tank is only 20 inches deep, and the MH arc spot (for lack of a proper name) is 5.5 inches above the top of the tank and each arc spot is 17 inches from the side of the tank - which puts each of them 7 inches from the center of the tank. When I turn them on individually, I get light focused across 2/3 of the tank on the side where the light is dropping off on the other 1/3 of the tank. I tried to find information on coral requirements for the length of time for lighting, but didn't have much luck.



What I am considering:

• 5:00 AM Actinics on
• 5:15 AM MH1 on
• 10:15 AM MH2 on
• 10:20 AM MH1 off
• 12:00 Noon Actinics off
• 3:10 PM Actinics on
• 3:15 PM MH2 off
• 6:00 PM Actinics off <-- need time to feed after work

This provides 5 hours for each side with full MH and 5 hours with reduced MH. With cloud movement in the tropical areas where coral reefs exist, they must have reduced sunlight a lot of the time. I'm not sure about the Actinic requirements, but like them to usher in and out the day.

ALL replies would be much welcomed!!

Jimmy Many Thanks!!

 

Hi Adicus

the actinic T5s wont be contributing much to your electricity costs
and as such leaving them on all day would be better IMO

additional your lights going off at 6pm does seem to deprive you of quality viewing time during evenings if you work conventional social hours

I have mine come on at 9 am and go off at 9pm for this reason

you want 12 hours (about) with the actinics and 10 hours with the MH
but with the MH you could consider running 1 for the full 10 hours and the other one for 8 so it comes on 1 hour later and goes off an hour earlier than the 1st one

it only saves you 2 hours of the running costs of 1 lamp , but at least doing it that way you are using a light cycle that has proven effective for the maintenance of the corals you want to keep

Steve

 

Steve - Thanks for the advise I was afraid that 10 hours was the magic number.