Photoperiods?

I recently (this past weekend) made the switch from PC lighting to MH/VHO lighting because I finally finished my canopy. The tank is a 90 gallon and the sump is located in the basement and is 55 gallons, so heat issues should be minimal.

I went from 260w of PC to 720w of MH/VHO (dual 250 MH 10k, dual 110 VHO actinics)

I am wondering how long people leave their "daylights" on for. I have heard and read many different things on this and have thus far planned on leaving them on for about 7 hours a day (with sunrise and sunset being an hour each) after the corals are acclimated to the increase, for a total of 9 hours of light each day.

Too much? Too little?

 

what I'd do but I don't have a MH solution yet so hopefully someone else can chime in

 

I get by with 6hrs aday with the 400w M/H and 16 on the VHO's At the coral shop we run them M/H 14 hrs ad and the VHO 18 hrs aday in the winter and summer the suns helps lower the time the M/H run. But like I said 6 hrs will most likley do just fine and the VHO will do there jobs at about 14 in a home aquarium.

 

I run my MH`s for 6 hours and my CF for 12, then my LED`s at night. I dont think you need to run your MH`s any longer then 6 hours, 4-6 is good, anything over that is just dumping heat into the tank and useing unwanted electricity, IMO. I have a 90 as well with 765 total watts. 2/ 250 MH and 4/ 65 w PC with the rest made up from the LED moons

 

I my self run MH's.
I would suggest no more than the amount of hours you are running now,
7 to 8 hours seem to be the amount of time every one i know here.
I used to run like 10+ hours a day but Ive seen no diffrence in coral health
running them more. ( if not better )

And i would start to get brown diatome algae when the photo period was longer than 8 hours.
Ive had no problems running 7.5 hours daily now for the last 2 months+ i would say.

You'll save money to and less agravation from nuisence algae's that seem to thrive on all that light any ways.

 

Sounds good, thanks for the replies everyone!

 

Either you do not have a diatom bloom and some other problem ? Or you do have them and you have a water parameter Issue ? Lighting period would have no effect on the diatoms they are feeding on your water's problem.. After the initial cycling and a new set up diatoms are gone for good . Unless you keep adding a life giving carbon source for them to live off of You may want to check in to your own water problem's if it is indeed diatom blooms ?

If your theory any coral culturing system's like the one that I manage or any of them would be over ran with a diatom problem as we run lights almost 24 a day . to generate the corals growth. I've never had or have a diatom problem there or at home once they where gone at start up . ;D

 

I haven't had any diatoms since after they died after my tank first cycled either. Maybe you have a different problem due to bad water parameters, wildreef...

 

well the brown algea get's on no where but the back glass, I did how ever cut down on photo period ( amount of time ) and thus it seems to greatly reduce the diatome issue.

Would you think something else might be causing it ? such as ?
Over feeding has not been an issue.

The only thing i can think of is the MH/'s bulbs need changing, they are getting some time on them. ( more time on'em than i want )

 

If you have diatoms ? in your system stimulated by the lighting period I know you have a water issue What it is ? Diatoms are very specific and particular as to what they use for a food/energy source , As for what maybe causing your problem ? I have not a clue maybe its your water filtration system, for the water to fill the tank ? As for bulbs age ? I run mine two yrs mine here are 18 months old now