how long

[dan]

when it's all said and done how long are mh to be on? i have 2-250-10ks and 1-250-20k and 4-4ft vhos.i've had them on my tank now for two months.i started with 2-10ks for 30min. a day for a week then bumpit up 30min.every week. 20k started 1hr.a day for a week then bump it up 30min.every week. is this right or wrong???????

[oceancube]

well ideally i think 11-12 hrs a day, i have mine on a timer, from 10:30am to 9pm, im gonna add an actinic so i can leave it on 30-45min after the mh, that way i can trick the fish and corals, they'll think there really in the ocean!(I HOPE)

[alexwolf]

Man, if i ran my lights that long my tank would be 100 degrees!!!! :confused:

[Instar]

10K's for 8 to 10 hours, 20K's 10 to 12 hours, VHO actinics for 12 to 14 hours, VHO (or if someone uses pc's) actinics bracketing the 20K by one hour in the morning and one in the evening. VHO actinics at 14 hours is most like the tropic day length and what most of the really great tanks that make tank of the month are at. Thats my 2 cents worth. There are many variables between setups, brands, distance from the tank, plexiglass shields, fans, bulb age, etc. that make an impact on the scheme of things. Starting out like you did is good although I think that when you change bulbs in a year (brand depending), I wouldn't go back to starting at 1 hour again as thats not enough length for photosynthesis.

[dan]

Larry :thank you for your 2 cents it's exacly what i needed.on the 4 vhos would they be all actinics or two actinic and two whites?

[captexas]

If you are just adding the halides to an existing tank it is good to start off slow and slowly increase the time they are on so the tank inhabitants can adjust to the new brighter light.

I have 2 VHO's and 2 halides on my tank and I run the VHO's for 12 hours a day and the halides for about 8 hours. Of course the VHO's come on first for a few hours before the halides come on and they turn off after the halides. I have the halides run a little later in the day so that hopefully I get a chance to get home and see how the tank looks in full light.