too much light?

[drakave]

is there such a thing as too much light for a system? thinking of buying a retrofit kit of mh. i have a 20 gallon long and was going to purchase a 175 watt system but thinking of getting a 250 because i know ill eventually buy a bigger tank. but if i get a 250 bulb thats close to 12.5 watt per gallon. what should i do? even at 175 thats close to 9 watts per gallon. thanks

 

[crystain]

I've been wondering the same thing about my 20 gal. tank. But I only have 2 x 55W lights, and it seems too bright.

 

[wolfpack]

You can absolutely have too much light if you were most interested in keeping any invertebrates with zooxanthellae. Too intense of light can be a quicker death for corals that anything else. Not only will you have to deal with a massive increase in tank temperature, but most coral will probably bleach and burn due to the excess of light. I've heard that 4-5 watts per gallons is good, with a little more being good for very light loving corals, but 12 seems very excessive.

 

[volitan]

Why don't you upgrade your tank before you upgrade your lights?

 

[adrian]

Yes there is such thing as too much light, but I dont think thats the case in either of the above tanks, the watts per gallon rule, again , is worthless, but for the record I have 13.6 Wpg, and know several who have way more, yes corals can be affected by the affects of over heating due to a lot of light, or if they are not acclimated properly to the brighter lights, but some corals can handle more light than one could ever provide, of course it really comes down to what kind of corals are in question, and placement of these corals, some corals that come from very deep waters that do not appreciate a lot of light, Trachyphyllia sp. for example, may be harmed by too much, then again some corals such as Acropora sp. may actually prefer a 400 watt MH to a 175 or 250. HTH