want to upgrade bulbs, really need some help here

[LyndaB]

I got an unexpected work bonus, so it may finally be time to upgrade the lighting on my tanks.

I have a 75 gallon and a 46 gallon bowfront that I would like to turn into planted tanks. My 16 gallon RCS tank seems to do fine with its existing lighting and the low light plants I have in it.

I have no idea where to start or what I should be looking for. I don't want lighting so bright that it frightens the fish or burns my eyeballs out, but would definitely like the wattage/bulb I need to grow some medium-high level plants.

Please give all the suggestions you can think of. I am seriously starting out here without a clue.

Thanks all!

 

[blert]

IMO, T5HO dual bulb fixtures for both. It is much easier, and cheaper, to reduce the lighting of a fixture that seems too bright then it is to find out that the fixture you just bought is inadequate. You could go with one 6700k bulb and one "ColorMax" type bulb to keep the light around medium-ish. Jetajockey has mad knowledge of lighting so you might want to hit him up for some input before you buy.

 

[LyndaB]

Thanks for your suggestions/advice.

 

[LyndaB]

Okay, checked out my fixtures today. The 46 gallon takes 1 bulb, 20 watt, the 75 gallon takes 1 bulb, 40 watt.

I really didn't want the expense of entire new fixtures..... how about a 10,000K? Good? Bad? Not worth it for 1 bulb?

 

[blert]

Okay, checked out my fixtures today. The 46 gallon takes 1 bulb, 20 watt, the 75 gallon takes 1 bulb, 40 watt.

I really didn't want the expense of entire new fixtures..... how about a 10,000K? Good? Bad? Not worth it for 1 bulb?

Not sure about the 46g but it looks like you have the situation that I do with your 75g. I also have a single bulb 40 watt strip on mine, that is for a T12 bulb. When I inspected mine I found it had a T10 bulb in it. Guess what, a T8 bulb will work in it! I put a 32 watt 8000k full spectrum T8 bulb in mine and my plants are not dying and are actually growing. Plants in this tank are: Wisteria (yuk, looking for replacements), Rotala Rotundifolia (?), Hygrophila Corembosa "Angustifolia", Java Fern, Anubias, Crypt "Asia" (?), and Dwarf Sag.

What you want to look for is a "full spectrum - daylight bulb". As you go into higher "k" values the light will look more blue. Also, I'm not 100% sure but, a 10000k bulb has better penetration than a 6700k bulb, meaning your smaller plants should get more usable light.

Here's some pics of my 75g with a single 32w 8000k full spectrum T8 bulb. I think I would have to consider this tank on the low end of low light.

 

[LyndaB]

Fantastic information, thanks very much

 

[mohican]

The "k" value in bulbs is the spectrum value, not the penetration. Stick to 6500 to 8000, best for plants. The penetration depends on depth and the water column itself. Lighting can lose up to half the potency just passing through water column. I recommend nova t5 ho. Def. go HO.

 

[blert]

The "k" value in bulbs is the spectrum value, not the penetration. Stick to 6500 to 8000, best for plants. The penetration depends on depth and the water column itself. Lighting can lose up to half the potency just passing through water column. I recommend nova t5 ho. Def. go HO.

Yes, I know. It is actually indicative of the perceived color of light output, not necessarily the spectrum. You can have full spectrum bulbs of 3000k, 6000k, 10000k, etc. But, it has been said that 10000k has better penetration than say 6000k as bluer light can penetrate deeper into water. As I said above, I don't know if this is 100% true or not.