[Dempsey]

Hello All,

Quick question. It might also be opinions I'm looking for... Or experience.

I replaced the 2 old 65watt 10,000K bulbs with 65Watt 67K bulbs. Now I have 4 new bulbs on my 75g. 2x65Watt 10Ks and 2x65watt 67Ks which brings me to 3.4wpg of CF.

I have heard people say that I(whom ever)should stagger the lights. For example, 2 67Ks come on at 3PM, then followed by the 2 10Ks at 6PM, Then the 10Ks go off at say 9PM, followed by the 67Ks turning off at 11PM. Is 3.4wpg of CF too much for the whole 8 hours?

I am injecting CO2. Is this just a power consumption concern or is that just too much light for the whole 8 hours? Or is it an algae issue?

Thank you all for your replies!

EDIT: I just installed the standard coralife legs to the fixture. So, the lights are now lifted four inches from the top of the tank and about 6-7 inches from the water.

 

[OverStocked]

Is your tank rimless? If not why is the water level so low?? 3.4wpg on a 75g tank seems to be a lot of light.

 

[Dempsey]

I don't think I worded that right. 6-7 inches total. with the legs and the water level from the top of the tank added together.

No it's not rimless. It's not low, it's right above the bottom of the top frame which is about 2 inches. You can't see the water level from the viewing panels.

 

[Dempsey]

BTW, the example above about the lighting times is what I am currently running. So far things seem to be going good for me. I know people say, "Do what works for you". With my photo times(which I plan to increase later), assuming I have proper CO2 and ferts, With 8 hours total of light, does anyone object to 3 hours bursts of 3.9wpg? Should I increase that to say, 4hrs? Figuring the begining and end of the photo period is 1.7wpg.

 

[FSM]

Power consumption doesn't really matter. Stop worrying so much about WPG.

This is a useful chart
http://www.plantedtank.net/forums/lighting/97622-par-data-selecting-t5ho-light.html

6" from the water, plus probably around 18"of water depth (somewhere around there, because a 75 is 20" tall, but it isn't completely filled to the rim, and there is substrate at the bottom). According to the chart, 1 PC bulb would produce about 30 PAR at 24". 2 bulbs running parallel should therefore produce about 60, which is medium light.

 

[Dempsey]

Thanks FSM! I will look at that chart now. I know i don't have to worry about the WPG so much... I just needed input. Besides that, it looks awesome with all 4 bulbs on! Actually, 2 of either look awesome too!