[wdeertz]

I am switching out my flourescent bulbs to metal halide. My reef tank is 160cm x 70 cm x 70 cm (approx 800 liters). Is there a general "rule of thumb" as to how much wattage is necessary per liter and/or depth of tank? I was thinking of 2 250 watt bulbs hanging above the tank in pendant fixtures but am concerned this may not be enough light.

I searched this site but couldn't find any specific mention on how to determine proper lighting. Any suggestions appreciated.

 

[Geoff]

Welcome to the TRT!!

ahh, the lighting question. it is best to figure out what you want to keep in the tank first. 250w lamps are a great all around wattage to keep the most varied critters. what is in the tank now? if you switch you would prolly need to adjust the critters slowly to the new lighting. the higher the wattage the longer the adjustment period.

with mh you may also run into tank heat issues. they produce a lot of pinpoint heat, and are able to raise the aquarium temp several degress.

G~

 

[Krux]

ack the metric system! my head hurts!

70 cm, that is like 24 inches i think. as stated above, 250 should be good for most stuff. if you really want to keep clams on the sandbed or some of the really intense acros, you might consider 400 watters, but also as stated above, you will need to watch temps of your tank. does your house have air conditioning? if so and you keep the room at a decent temperature, that should help a lot on keeping the tank heat down.

it is us uncivilized oregonian folks who have yet to discover the wonders of air conditioning that have tremendous heat issues.

oh, and also keep in mind, you can look into doing 400watters in a pendant type setup and elevate them a bit further off of the tank than a regular hood would allow. just don't go too high or you will end up getting the same light as if you mounted 250s closer.

 

[Prismaco]

Well I have:

1 96w 50/50
1 96w 10K
1 175w MH 10k

for my 37g show tank...

-Paul

 

[LittleFishBoy]

it is us uncivilized oregonian folks who have yet to discover the wonders of air conditioning that have tremendous heat issues.

No kidding!!!! Im with you on that one.

 

[MontanaRocknReefer]

Like Geoff has stated it depends on what you keep! I don't get caught up in wattage per gallon but more on what you plan to keep and intensity of light required for the area you are going to put the coral! I have 2-250ww MH 10,000 German and 2-96ww PC's actinic 03 on my 80 gallon reef and figured I can keep most everything except a few sps corals!