Yikes! Aqua-Gro = Big $$$

[manytanks]

We've got a 55-gallon planted tank with twin light hoods, each supporting a 15-watt flourescent. I realized it was way past the time when the bulbs should be replaced and went to Home Depot to get one of their nicely low-priced 'plant and aquarium' 15-inch, 15-watt  bulbs at about $5.00 each.

"No way," said wife Tanksalot. "They're not really for growing plants in an aquarium; just for looking at them. You need to get a real plant grow bulb". So I went to our friendly neighbourhood SuperPet in Kanata and bought a 15-watt, 15-inch Aqua-Gro flourescent bulb...priced at $20.00!!!  Yikes.

Question: Is this the going rate around town for these little really-for-growing-plants bulbs? Or is there some place where I can get a (much) better deal? I haven't bought the second one yet...

[luvfishies]

Save your money and don't get the second bulb in a lfs.

All you need is a bulb that is 5,000-10,000K. Doesn't matter if it's labelled "plant" or not.

I think it's GE and Phillips that have ideal plant-growing bulbs, at Home Depot for about $5 each.

[darkdep]

Unfortunately, 15" is an unusual size.  You might have a hard time finding a decent bulb at HD (18" yes, but phillips doesn't seem to make 15" bulbs).

[manytanks]

Thanks for the advice. You're correct: I got the size wrong - it is an 18" that I need. But the only 15-watt, 15" bulb sold at Home Depot is a ~$5.00 Phillips "Plant & Aquarium" flourescent with a colour temp of only 2700K...and there's a considerable & visible  in-the-tank  difference between the $20 SP AquaGro and these ones. The lower-K bulb makes the fish colours look much nicer, but the AquaGro is easily much brighter.

Can anyone suggest any other sources in town of more reasonably-priced 18", 15w grow-lights with the needed colour temperature?

[BigDaddy]

Just get any 18 inch bulb you can find.  As luvs indicated... over 5,000 K is better ... but any bulb will do.  I'm pretty sure you have a 15W 18 inch bulb... that's standard.

Recently, it's been determined that the color temperature of bulbs (like your "specialty" Aqua Gro) has very little impact on plant growth, less than 10%.  So, save your money and buy 4 regular ones and change them out every 6 months to a year and you will get a lot more plant growth than you would out of your 20 dollar Hagen bulb.

[manytanks]

Thanks, Big D...just what I was hoping to hear.

And if I may, an additional word of thanks and acknowledgement for all of your posts and advice. They never fail to clarify and enlighten. I learn something from everyone who contributes to this excellent board...but if there was one person whom I would single out as an OVASian Zen master - especially regarding planted aquariums - that'd be you.

[luvfishies]

Manytanks, do you have only the 2 bulbs, or do you have 4?

If ti's only 2, it doesn't matter too much what bulb you get as there just won't be ENOUGH light to grow anything but the most undemanding plants. You'd have less than 1 WattPerGallon (30 watts over a 55g).

To really get things growing you'd have to increase the amount/wattage of the bulbs, which in this case means totally revamping your lighting hardware/hood.

[darkdep]

If it IS 18" that you're after, I actually went to HD today and confirmed that there are many 18" bulbs available there, including my current favorite, the Phillips Daylight Deluxe.  It's a 6500k bulb and produces a beautiful light.  Cheap, too.

[manytanks]

Thanks, Luvfishies. Actually we have stocked the tank with mostly undemanding plants, including anubia (some flowering!), vals, cryptocornes, java ferns and some (sad-to-say quite sorry-looking but valiant) swords. Aside from the swords, everything is doing quite well and seems to be on the grow, although it has been a patient process. Interesting to note that excepting for the last few weeks, we haven't been fertilizing, either. And although generally it isn't required with the wattage you point out, we've been adding DIY CO2 all along, which seems to have been helpful. The substrate base is also 100% clay kitty litter (no additives) if that's of interest, hasn't seemed to have had a negative effect on anything  in the 1+ year this tank has been up and running, and it was something we wanted to try.

Thanks DarkDep - I'll check out our local Home Depot and see if I can't get a slightly brighter 18" bulb than the Phillips one I mentioned above.

[manytanks]

Here's a pic of our low-light, 30 watts per 55-gallon tank with our endlers, neons, corys, sae's and one lone shrimp.

[RoxyDog]

this answered some questions for me too, thanks everyone.  just wondered though ...as long as the bulb is the right length to fit in your hood, then does it matter what the wattage is?  as in, my hood currently has 2 20w bulbs, can I just replace them with 2 30w bulbs without any effect on the hood?

[RoxyDog]

this answered some questions for me too, thanks everyone.  just wondered though ...as long as the bulb is the right length to fit in your hood, then does it matter what the wattage is?  as in, my hood currently has 2 20w bulbs, can I just replace them with 2 30w bulbs without any effect on the hood?

[Mettle]

Ususally bulb lengths for the smaller ones are correlated to wattages. From what I've seen, anyway... But you may want to check what your ballast is capable of holding. Just like a lamp that would only accept 50w bulbs, you don't want to cram a 100w in there. Bad things can happen.

[darkdep]

(Except for a few rare examples)...

Fluorescent Bulb thicknesses/lengths correspond to the wattage.  An 18" T8 flourescent is always going to be 15watts, that's just the way it is (it's not the same in the incandescent world).

manytanks:  There ARE different "lumen" ratings for different bulbs.  The standard cheapo Phillips bulb is more of a "utility" grade and has a rather low colour temp (somewhere in the 2100k range if I remember correctly) and doesn't have a nice white colour.  The Phillips "Daylight Deluxe" bulbs come in a cardboard sleeve that identifies them, very close to the "Aquarium and plant" bulb (which is crap, btw).  The Daylight Deluxe bulbs rock.

An option...I had a traditional fixture on my 30gal with a single 20watt 24" bulb in it (Another unusual size).  I didn't like the light output, so I took my tools out and completely dismantled it, removing all the guts and leaving just the shell.  Now that I had it cleaned out, I was able to attach two sets of fluorescent endcaps (from HD), wire in a new electronic ballast (again, from HD) and put in 2 25watt bulbs.  So I was able to go from 20watts to 50watts, use less expensive (but good qual) bulbs, and my fixture looks the same.

If you're interested in this, lemme know, I can post pics.

[manytanks]

Darkdep: yes please, pics would be great. No problems with space (for two bulbs instead of one) or additional heat?

[BigDaddy]

Just a quick correction darkdep.

Lumen is how bright the light appears to the human eye.  Temperature (measured in Kelvin) affects what colour the bulb appears to be.

And yes, the standard bulbs are usually 3,000k.  That give a tank a very yellow/red look to it.

Be careful when buying bulbs.  I have seen "Daylight" bulbs which were actually rated at 4,100K.. which is actually "Cool White".  Daylight should be anything over 5,000K (I've seen 5,000K, 5,500K and 6,500K bulbs all sold as "daylight").

[luvfishies]

Here's an easy mod to Double your light output:

http://www.boognish.org/ripvan/fishdiy/

[UCGrafix]

Litle trick,

If you have a double tube set up, buy a normal cool white and warm white, and set them up together, it will give you the full UV spectrum.
I'ts been tested under a light and UV meter.

Change them on a regular basis, if the light says good for 1,500 hours, go half that, don't wait until they burn out, and they will keep there full strenght in UV rays.

That's what most indoor plant growers use, it's cheap and does the trick.

Denis

[darkdep]

manytanks:  No issues.  The old fixture setup had the ballast inside the fixture, along with a double layer of plastic and inefficient usage of space.  When I removed all that, I had lots of room for the 2 bulbs, and bolted the new ballast to the back of the fixture.  No heat issues.

Bigdaddy:  Yes, thank you.  I keep screwing that up.  :wink:

The link posted by luvfishes is pretty similar to what I did, but mine looks a bit different.  I'll post some pics.