Increased my light output 4X for under $50

[Mustang5L5]

Figured I'd share my experience with others as I looked for a post like this not too long ago.

I have the standard stock hood lighting on my tank. It's a 30" long tank with a 24" 20W bulb. It gives me roughly 0.54 Watts per Gallon. Most of my plants are low to medium light such as Java Fern, Anacharis, Hornwort, Amazone Sword and other varius swords. I was getting growth, but VERY slowly.

I wanted to increase the light over my tank but did not want to buy a $200 hood kit now did i have the time to design a custom hood that would look good. I have two over-the-side filters so i just didn't want to deal with trying to constuct it.

What i wanted to do was retrofit TWO 24" 20W bulbs and overdrive them to equal roughly 80W. That would give me about 2.17 WPG and put me in a good range for the plants i have.

This is my directions
http/www.plantedtank.net/odno.html

So i took a trip to Home Depot and they have a good assortment of Ballast kits. I bought this kit:
GE Ballast B432I120RH (4) F32T8 $27.xx

I also bought 4 of the end-cap bulb holder thingys for $3 total and of course i had to get another bulb which was $14 or so.

I gutted the stock hood, mounted the ballast on the outside on the backside and bolted the end-caps to the inside of the hood using nuts and bolts. I ran the wiring all nice and neat. Now, i haven't done this yet, but since these bulbs will be putting out a little more heat, i plan on getting a PC-style 120volt electric fan and mounting it to one end of the hood and slotting some holes in the other end to draw air through. That should keep things cool. I also do not have a reflector inside it right now. I need to make another trip to home depot and pick up some AL or something and use some tin snips and mount it as a reflector. When all this is done it should be less than $50

Here are some pics

Stock 20W lighting with reflector

Two 20W bulbs overdriven 2X each without reflector

Notice a difference??


I'm sure there are other ballasts you can use to Overdrive some 12" or 18" bulbs as well. It's just that in my case i needed 24" bulbs.

 

[mr_br0kn_drmz]

woah thats what i should do.... . thanks for the info mustang. i am definitely gonna look into this.

 

[marks69]

i just did a light for my 55. i bought an electronic ballast for 3-32 w t8 bulbs, endcaps, and 3 bulbs.built a frame for it for about $10.i have some metal for a refector, but haven't done that yet.
before i had 2-15w bulbs in my standard light hoods, now i have 96.
total cost about $60.
and i still have room for a few more, but wanted to increase slowely.
i could overdrive with another balast for about 15 bucks, but i don't know if my plants will need it yet.

 

[Great Lakes]

A couple of notes on overdriving. First I am all for it.

Now for a few clarifications on Mustangs posts.

Only use Electronic ballasts for overdriving, never magnetic.

They should be wired in parallel, not in series, ie; two wires to each bulb, not four wires to one, if using two bulbs. I have run four bulb ballasts succesfully on one bulb.

On output. Efficiency drops when overdriving, ie; normal, 95% = 19 watts with a 20w bulb, 2x overdrive, 85% for 34 watts, 3x overdrive, 80% for 48 watts, 4x overdrive, 75% for 60 watts.

Still a lot of light for on the cheap though.


GL

 

[Mustang5L5]

Anyone know the expected bulb lifespan? I realize overdriving will shorten it, but how long can i expect them to last?

 

[drobbins27]

Looks amazing my friend. thanks for the idea

 

[Great Lakes]

Believe it or not, there is na appreciable shortening of lifespan. Between 8 - 12 months. Your spectrum will start to shift at this point.

GL

 

[fish_r_great]

Could you post some pics of the light and what the finished prduct looks like?
THX

 

[sinistral]

They should be wired in parallel, not in series, ie; two wires to each bulb, not four wires to one, if using two bulbs. I have run four bulb ballasts succesfully on one bulb.

It's too bad I missed this post in early March when I was on vacation and actively looking for a DIY lighting project for my 29 gallon.

One question: it's been a long time since physics and EE for me, but in Mustang's diagram aren't the bulbs wired in series? What's the downside of wiring in series?

Thanks in advance!

 

[Great Lakes]

Now you are testing me....

I believe it has something to do with the resistance. Two bulbs in a series on four wires take greater effort, (amperage), to run than two bulbs on two wires each.

It makes sense when you look at it.
1 bulb on two wires x 2 is the same theoretical output as four wires to two bulbs in a series. Except in series the circuit has a longer distance to travel, drawing more amps and reducing power output.

GL

 

[rollntider]

Now you are testing me....

I believe it has something to do with the resistance. Two bulbs in a series on four wires take greater effort, (amperage), to run than two bulbs on two wires each.

It makes sense when you look at it.
1 bulb on two wires x 2 is the same theoretical output as four wires to two bulbs in a series. Except in series the circuit has a longer distance to travel, drawing more amps and reducing power output.

GL

not to mention in wiring in series, a votalge drop could occur as one bulb weakens(one being brighter and more voltage applying to one causeing shorter life span of the bulb). plus if one bulb goes out they both go out in series.(I.e. tiny xmas lights) (pays to be a former electrician)

 

[sinistral]

Now you are testing me....

I would never test a mod or an admin!!! My trust in their knowledge is implicit!

1 bulb on two wires x 2 is the same theoretical output as four wires to two bulbs in a series. Except in series the circuit has a longer distance to travel, drawing more amps and reducing power output.

This does make perfect sense to me. Brings me back to AP physics, it does. I'm seriously considering doing this...my main worry was that I'd wire it in series and it would explode. Instead of running that risk, I'm going to initiate the project and ask one of my EE friends to help out with some advice.

Seriously, thanks for the reply GL, that cleared up my confusion and pointed me in the direction of recruiting help so I won't kill myself or my fish.

 

[sinistral]

not to mention in wiring in series, a votalge drop could occur as one bulb weakens(one being brighter and more voltage applying to one causeing shorter life span of the bulb).

Ahhh, that makes sense to me too.

plus if one bulb goes out they both go out in series.(I.e. tiny xmas lights)

I don't think my family has ever owned series xmas lights, although I remember in an episode of Happy Days the forgotten brother Chuck went through a whole string of lights to try and find the bad bulb until Fonzie pointed out that maybe it was the test bulb that was bad...

Ok, that was a digression.

(pays to be a former electrician)

I don't suppose I could convince you to do a little consultation work on a project I'm thinking of doing... j/k! B)

 

[rollntider]

I don't suppose I could convince you to do a little consultation work on a project I'm thinking of doing... j/k! B)

You can always PM me, I can always see what I can do

 

[Yenko]

This is definitely an option for me. The only problem with the cooling fan idea is the evaporation it will cause. You could put the ballasts outside the canopy and have a fan blowing across them. I don't think you have to worry about excess heat from the bulbs, either. If they have 75% efficiency when overdriven to 80w, then, that's only about 20w worth of heat being produced. The only issue is the heat from the ballasts.