Is 2x250 MH enough?

[pawnman]

Hi, I am sorry if i posted this twice. I am new to the sight and could not find the first one I posted. I have a standard 55 and have recently bought 2x250 MH lights. This tank has been running for about two years on 2x96w 50/50 smartlight pc's. I would like to use 20k bulbs (I like the color). Should I use both of the pc's for the atintics? If so what wattage :? should be used? I know the 20k will not promote coral groth as well as the 10k, will this hurt my ability to maintain a healthy tank? Also should I intrduce the new lighting gardually or go full blast from the start? I would like to be able to keep anything I see and think is cool. Thanks for any info you might give.

 

[scuba_steve]

welcome to aa

yea the 250 will be fine !! i would use the pc for antinics even though the 20k will be blue !! whats in the tank now?? if just fish id prob be safe and run an hour on hour off for the first week

 

[Bearfan]

2x250=500
2x96=192

500+192=692

692/55=12.58 WPG Now

192/55=3.49 WPG Then

I would say you might want to introduce that big of a jump slowly, but maybe someone else knows better.

 

[malkore]

I'm just a noob, but my book says the same thing Bearfan says: when increasing light intensity, do it gradually over a week or so. New strong lighting can melt many soft corals.

 

[pawnman]

Thanks for the advice everyone. I have a couple of soft corals right now and that is it as far as corals go. I assume this change will enable me to keep anything I would like to have?

 

[pecan2phat]

Use the PC lights to obtain a dusk to dawn effect with actinic only bulbs. You can set the PC lights initially to a 12 hour schedule (if that is what you had before and or prefer) and start off the MH lights at 2 hrs for a week, then 4 hrs 7 days later, then 6 hrs on the 14th day, finally at 8 hrs on the 21st day.
Food for thought though, most people using 20k MH bulbs with VHO or PC supplements end up using 6700k white bulbs to offset the intense blue of the 20k MH bulbs. If you go this route, then I would scrap the dawn to dusk effect (though I personally like this) and have all the lights turn on the same time while still adhering to the acclimation schedule. HTH

As for what you can keep, yes you can definitely keep any softies, LPS, clams and SPS. Though with SPS, you will need adequate water flow and calcium levels. I would suggest a calcium reactor for a heavily planted SPS tank.

 

[cj10488]

start off the MH lights at 2 hrs for a week, then 4 hrs 7 days later, then 6 hrs on the 14th day, finally at 8 hrs on the 21st day.

Anytime over an hour you have already done damage to the coral... Altering the photo period like this will stress the coral out even more.. The best way is to set your schedule... Go to the Local hardware store and get yourself some Windows Screen (fiberglass stuff) take about 4 or 5 layers and cover the top of the tank.. Every 3 or 4 days remove a layer and let the coral adjust for another 3 or 4 days... The window screening will give them the full photo period with a dramatically decreased intensity... If a coral starts looking stressed after you remove one layer of the screen you can always put it back on... I have as well as others sucessfully used this methods on many ocassions..

HTH<
James