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spikehs
11-07-2003, 04:17 AM
I just bought 2 400w ballast from venkiw for my 55 gal (36x18x18) I decided to go with the 400w cause there really wasn't that much diff and price + these will server me down the road when i upgrade to a bigger tank. I guess the question is (assuming I can keep heat under control) do you think 800w + actinics is too much for a tank (I want mostly sps). Thanks.

Buccaneer
11-07-2003, 04:40 AM
There is a guy on RC ( Lunchbucket I think ? ) and he has MH over a 20G :eek: ... you watched " Tim the Toolman " did'nt ya ? MORE POWER ! :cool: :smile: :razz:

Besides once this hobby gets in your blood there is the inevitable tank upgrade right ?

Cheers

StirCrazy
11-07-2003, 04:50 AM
I think you will be fine as with the 400 watts you could put your bulbs 12 to 14" abaove your water line and this alone would help keep the heat down.

I raised my 250HQI's up an aditional 3 inches when I put the tank back tgeather and I now have no cooling fans running and I am only getting a 0.5 degree temp change where I was getting 2.0 degrees befor with two fans running.

Steve

spikehs
11-07-2003, 05:26 AM
oh the tank upgrade is DEFINATELY inevitable, just a matter of when and how many times bigger :mrgreen:

Reef_kid
11-07-2003, 05:55 AM
i did 250 watt over a 25 gallon and that was 10 watt per gallon the only problem was the evaporation. its a pain without a top up.!!

Delphinus
11-07-2003, 05:55 AM
It's probably more light than you need, but there probably isn't such thing as too much light. My old 20g was lit by a 250w and it did OK for its time.

There is such thing, however, as light shock from going from one intensity to another. To go from 175W to 400W will take some ramping of the photoperiod in order to prevent UV burn.

A few years back I once had a 175W bulb crack and the outer globe slid partially off the bulb, leaving the inner arc tube partially exposed (and still lit). Even though I happened to come for lunch that day and noticed right away (so it was only about 1 hour on the tank since the light would have come on at 11am), pretty much everything that was underneath that bulb (that couldn't hide) was fried. I did lose several pieces of acro including a gorgeous purple acro that looked just like Sam's does now in his picture thread. I never again did find one that looked quite like that, but seeing Sam's purple acro now after its colour change reminded me of this whole story which I had almost forgotten about completely.

Delphinus
11-07-2003, 05:57 AM
i did 250 watt over a 25 gallon and that was 10 watt per gallon the only problem was the evaporation. its a pain without a top up.!!

So true. And a lot of evaporation in an environment not designed to carry away humidity can be a whole lot of fun, too. Something to think about.

spikehs
11-07-2003, 01:54 PM
There is such thing, however, as light shock from going from one intensity to another. To go from 175W to 400W will take some ramping of the photoperiod in order to prevent UV burn.


Thats the only thing i was somewhat worried about, I was thinking for the initial frags i get I would start them out @ 5 hrs, the bump it up 1 hr untill i get to 10-12...does this sound reasonable or overly cautious? then when i get others later on, I would turn off one side and do a similar sort of thing.

Delphinus
11-07-2003, 03:36 PM
One technique that you can do is keep your photoperiod at 12 hours, but the light is never on for more than, say, 1/2 an hour or so. So half-hour on/half-hour off/repeat 11 times; kind of thing. Then after a week it'd be like 45 minutes on/15 minutes off/repeat ... and so on ... gradually ramping up to a full 12 hours on (or whatever photoperiod you're going for).

Another thing is to raise the lights temporarily and lower them gradually every few days. Might not always be practical though, who knows. But it works pretty good!

I've also heard about using eggcrate on the top of the tank, or even stacking eggcrate. Creates a wee bit of shade and you pull away a layer when it's time to ramp up. Never tried this method myself though (I have tried the other two ideas up above and they worked out well).

StirCrazy
11-07-2003, 11:48 PM
I went from basically PC's to 250 watt HQI's and because I couldn't raise the lights, what I did was an on/off routine as recommended by Eric Borneman.

The way I did this was one hour on.. one hour off and keep repeating for a 10 to 12 hour photoperiod. Then, after 5 days, change it to 1 hour 15 min on and 45 min off. After another 5 days, go 1.5 hour on, 1/2 hour off. And after another 5 days, 1 hour 45 min on, 15 min off and finally after 5 days go on all day. I never bleached anything using this method.

Steve

Canadian Man
11-08-2003, 04:31 AM
I agree with what Tony said and Steve. This is how I acclimitized my tank from flour....to halides. Worked very well.

AJ_77
11-08-2003, 03:56 PM
For Those Who Have Switched:
How big was the jump in wattages between the FL or PC and the new MH? Does this affect how long the on-off periods are as you ramp up, or is it more the quality/intensity of MH that makes this necessary?

I mean, if a person is going from 220W of PC to 250W of mh, would there be an issue (could you just fire it up)?

StirCrazy
11-09-2003, 02:30 AM
For Those Who Have Switched:
How big was the jump in wattages between the FL or PC and the new MH? Does this affect how long the on-off periods are as you ramp up, or is it more the quality/intensity of MH that makes this necessary?

I mean, if a person is going from 220W of PC to 250W of mh, would there be an issue (could you just fire it up)?

yes there would be a issue as the MH is much more intense. all the 250 watt means is how much power the bulb its self consumes to make the light. if you want to compare intensity you can look at Lumin. most PC's are in the 8000 lumin range. whare a 250 MH can be up to 20000 lumin (or higher) depending on the bulb so you can see it is 2 to 3 times more intense than a PC which means more light will penatrate through the water farther.

Steve