I have a few lighting questions.........

[fishfrenzy]

I have a 29 g FW community tank, with swordtails, molly, tetras, kuhli's, etc. I have 3 20watt bulbs. the big thick fat ones as the lighting. Anyway, i went to 3 different fish stores today to look for some new lighting but wasnt too sure what to get, they had 50/50 bulbs, 10,000k bulbs, 18,000k bulbs, actinic bulbs. However I couldnt find many 6500-6700k bulbs. would it be ok to mix different bulbs etc?? or should i stick with all the same kind?? I was thinking like getting a 50/50 a 10,000k and a 6500k. or whatever kind of combo....... i just dont know what to go with or if the higher K lighting is bad for the FW fish/plants?? I have 6-7 live plants that require moderate lighting!! Please help me anyway you can / give me any info. Thanks in advance......

[turtlehead]

50/50 a 10,000k is for reefs.

[fishfrenzy]

i know what they all are for but is there any reason not to use them in a FW tank??

[Fishfirst]

its a LOT of light for your freshwater tank

[DavidDoyle]

Actinic is only usefull for sw reef tanks. It will be almost useless on a fw planted tank. 10k is a fairly cold/bright look and if you like it, you can use it for plants although it is not the optimal choice0 6-7,000K is preferred by most. Daylight is about 5,000k going up from there looks more "white" while going down looks more "yellow" (as in tanin stained water).

You can mix bulbs. Ideally put the higher K one on the back of the tank and the lower K over the front. In fluors my personal favorites are Triton full spectrum tri-phosphors (unfortunately their 24 inch bulb is a T-8, the thinner one). They are expensive but only need to be changed when they burn out and last about 1.5 years. They also make fish colors really pop. Regular fluors on planted tanks should be changed about every 6 months to maintain optimal lighting and they degenerate in terms of plant useful spectrum even though the naked eye sees no difference.

I also use the GE Plant/Aquarium bulbs which are about 4,000K and I like the muted look and plants love em.

[fishfrenzy]

thanks david for the reply, I work for a full spectrum lighting company called natural illuminating technologies. we make lamps for ppl with seasonal affective disorder SAD. Anywho, i have access to ALOT of different bulbs. the only reason why i asked about the other bulbs is b.c i like the way they make the tank look, i like the whiter/blueish look, but if those lights are bad for my plants than i prob wont get them. However, alot of the bulbs I use at work are 5500k and used to use one to light my 10g fry tank, which had nothing in it but gravel and a filter and after about a week had major green algae out break, since then i change to a 50/50 bulb b.c i like the way it looks and I havent had an algae prob since.

Yea i notice in pet-co today they did have some 6700k bulbs but they were T-8's. the ones i have now are T-12's. i am guessing as long as the spectrum is right the "T:" size doesnt matter?? however the wattage for the T-8's is lower than the T-10's or 12's. and i thought plant lighting went by watts per gallon?!?! thats why im a little confused. right now i have 3 T-12 20watt bulbs. the T-8's in the store were only 17-18 watts i think. its not that big of a wattage drop. i was just curious if it mattered or not......

But basically the 10k and 50/50 bulbs wont kill my plants if i decide to go with them?? I might use a 10k or 18k or 50/50 in the back and the 2 in the front closer to 6700k-7000k if i can find them. does that sound like it would be ok/work>?>?

[DavidDoyle]

Switching your 10 to 50/50 basically reduced usable light for algae by almost half which is part or all of why the problem went away.

You cant use t-12 in t-8 fixture. I have both types of 24 inch bulbs. Almost all 24 inch bulbs are the fatter ones. However, there are a few that are the thinner T-8s and are also lower wattage.

I suggest if you like the 10k look it is OK for the plants except in those high and very high light planted tanks (3 or more wpg). I recently decided to try a coral-life tr1-phosphor in a 24 inch, 20 watt bulb. It is cheaper than Tritons and looks nice, but not as nice as the Triton which wont fit in the twin bulb T-12 fixture.

Here is a good artice about lighting relevant to aquariums you might find helpful: http://www.geocities.com/CapeCanaver.../lighting.html