[givemethatfish]

Hi all,

I'm taking on my first real DIY project. I'm making a simple light fixture for a 20 gallon long tank with a versatop. Low maintenance plants, no CO2. My plan is to just install a pre-made T8 under cabinet light strip inside a section of vinyl rain gutter.

My questions:

1 - Should I install two slim light strips, or would one be enough? I don't want to overkill with light. I would be using 24 inch daylight T8 bulb(s).
2 - Should I install a cooling fan in the light fixture? I plan on drilling holes for ventilation, but I don't know if it would get too hot.
3 - If cooling fans are a good idea, I'd be using a pair of computer cooling fans. I would like to hardwire the fans to the light fixture so I don't have to worry about plugging in one more thing, so: if I get a T8 fixture and a separate plug, can I simply connect the wires from the cooling fans into the wire from the fixture and connect that to the plug? I have limited electrical experience, and I don't want to short anything out, etc. Of course I will be sealing everything very well with electrical tape and taking precautions that the connections are waterproof.

Any advice? Thanks!

 

[Kaduhn1]

You're going to spend more time and money on this than what a single t8 fixture cost. But if you are doing it because you want to then you should be able to search T8 par levels and there's probably a chart for it that will give you an idea if you need one or two. Two t8's would probably be better because you could move it up from the tank and get even coverage and still have enough light, no dark spots, if it's too much you take a bulb out. As far as fan's it wouldn't hurt by any means, cooling is always good. I have a dual 36" t8 that runs 12 hours a day on plants and it's barely warm but its not homemade. You'd also need to make sure the fans are AC like the lights will be, which they probably are. I'm getting out here on a limb but the voltage and amps on the fan probably need to be the same as the ballast for the lights in order to wire them together or they will fry. best bet is to buy a power adapter that you can change the voltage and just put it on one timer with the lights.

 

[PlantedRich]

Several small points on your question. I would think one t-8 would do for not getting too much light. Much depends on how far from the water as well as how long they are on.
For the fans, there are many ways to go with cooling. One simple way to hold heat down on any fixture is to move the ballast outside the cover. Hang it outside on the back of the stand, maybe? The ballast is often the main heat.
Running cooling fans along with the light is not a big deal either, if you like that way. Many ways to go with that. Depends on what fan you get, how you will want to wire it. If you want to hold plugs down, get a fan that uses the same voltage as the light. Normally 110AC in the US. The question of amps or milliamps used by the fan or light is not a factor. That just tells you have much the fan and lights might potentially use. Does not need to match each other. Only comes into play if you reach the upper limit of what wires or breakers might carry. Not even a question in your case.
Sometimes there are real values on small computer fans that run on 12volts DC. For those you might find a really cheap plug-in power supply (charger?) that puts out 12VDC. They might be found at Goodwill or thrift shops for a couple bucks. Just find a voltage to match and one that puts out at LEAST as much as the fan is labeled for amps or milliamps. The power supply and fan will carry labels for this info. Just look carefully and match the supply to the fan voltage and type. Just don't try to use a power supply putting out 10 milliamp to run a fan needing 60-80 milliamps?

For safe wiring, look at using heat shrink tubing to seal all the connections from water. Reasonably cheap and it stays in place much better than tape. Tape can unwind and come off after a while. Shrink the heat shrink with most any small heat source if you don't have a soldering iron. Candle, stove burner, cig lighter? :thumbsup:

 

[PlantedRich]

For the most simple, less involved, way to add a 110AC fan, a small drawing might help.

Take the cover off the light. You may find a couple connectors screwed on or crimped on where the ballast wires meet the cord wires. Unscrew or cut off these connectors and add the wires from the fan. Either fan wire to either light and cord wire. No Positive/negative polarity involved here. Joining at any point along the cord will do the same if easier.

 

[givemethatfish]

Thanks so much for the responses. That drawing was just what I needed. I wasn't sure if I could just connect the fan wires to the light wires or how to go about it.

I know it's not that expensive to just buy a light fixture, but I have about 20 feet of gutter left from just putting new gutters on the back of my house. I also already have the cooling fans, black krylon fusion spray paint for the outside of the gutter, and some leftover drawer handles from another project to add a little handle to the light to make it easier to move around. So it's really just the cost of the light strips, which I can get a 24 inch T8 at Walmart for $8. And I like the idea of making it myself too

So, it looks like the PAR of one T8 bulb 13 inches from the substrate is about 40. So one strip/bulb should be enough light for low-medium light plants, eh? I just have to keep in mind that the tank is 30 inches long but the light is only 24, so I will do the lowest light plants on the two far ends of the tank and just center the fixture.

 

[Kaduhn1]

Knew someone with little more knowledge would chime in. You got me looking now too, i need more light. Going two bulbs that are shorter than the tank would allow you to raise it up and still get good coverage and par. You can always get rid of par if you have too much but if you don't have enough to begin with your screwed. not sure if you can fit two inside one gutter though. Let me know if you can though also some sort of reflective material on the inside too. buy an actual reflector and cut and bend it to fit maybe?

 

[givemethatfish]

I got the "slimline" under cabinet T8 light fixtures, and you can fit two side by side in the rain gutter. I did a test fit. I can't raise the light fixture up much because of where the tank is sitting, but I figure I'll try it with one and if I need more light, I can just attach the other fixture. The inside of the gutter is white, and the PAR I looked up was for a T8 fixture with "typical white inside surface" which I assume doesn't figure in a reflector at all. The gutter vinyl is a pretty flat white, but if I needed more reflection, I could pick up some mylar ballons at the dollar store and line the inside of the gutter with the inside of the balloons.

 

[Kaduhn1]

Where did you get the fixtures from? I found these guys http://www.slimfluorescent.com/?gclid=CL_g9cyw070CFUVgMgodhiMALA and the 30" t4 would fit my tank perfect. it's 30" wide. Kinda odd with a t4 but the bulbs are out there for it.

 

[givemethatfish]

I got them at Wal-mart. Oddly, I don't see them on the website, but they were in the light bulb aisle and were either $8.47 or $7.49, something like that. They had them in 18 inch and 24 inch T8, slimline under cabinet lighting.

 

[Kaduhn1]

are you mounting the entire light inside the gutter your tearing the components out and remounting them? And using both ballast still or buying one that will do both lights?

 

[givemethatfish]

Since I'm trying it with just one bulb to begin with, I will probably just mount the entire light inside, with the plastic bulb guard removed. I may even just use those 3M strips to stick it in temporarily - not sure if those will hold with the heat, but it will be on a versa-top so if it doesn't stick it won't fall into the water or anything. I figure the less I fiddle with things, the less likely I am to break something or mess it up

If I end up putting both in, I will probably buy a ballast for both lights - although both entire lights will fit side by side as is.

 

[PlantedRich]

Small point to think over? If you use both lights and both ballast, it might leave it easy to run them on timers so that you could go with lighting in stages. One or both on? I like the idea of my fishing ligths coming up slower.

 

[givemethatfish]

I picked up corrugated plastic today for dividers (making a divided betta tank). I'm going to get started tonight by cutting and painting the gutter. I'll put up some pictures this weekend I have this grand idea in my head of this sleek modern-looking light. I hope it doesn't turn out too kludgy. I've also decided to skip the cooling fan and see how hot it runs without them.

I thank everyone for the advice!

 

[givemethatfish]

Just thought I'd come back and give an update. The light is working beautifully so far. I ended up just putting one T8 strip in for now, and I think that's all I'll need. I have ludwigia, ruffled swords, anubias, and water sprite in the tanks. I know none of them are particularly light-demanding, but they are all growing nicely and look really healthy. They are mostly trimmings from my higher-light 54 gallon tank, but the ludwigia even seems to be keeping its reddish hues.

It was warming up the water at the top of the tank slightly (though the glass was only slightly warm), so I took the feet from my Finnex Ray II which I wasn't using and screwed them onto this one. I wasn't using the feet I mean, I am using the light fixture on my 54 gallon tank. It raises it up about an inch which is just enough to prevent it from heating the water. Cooling fan definitely not needed.

So pictures.

#1 is the tank the light is on. I don't know why I took the picture in the dark because you can't really see the light fixture. It looks nice on top though. The tank is a 20g long and home to bettas Roland, Ender, and Elise who is the little cellophane double tail plakat you can see in the rightmost division (Elise is my daughter's fish, so she named him after herself. She's 3.)

#2 is the light and the hood separately. I just got some silver drawer pulls to make little handles on top of the light fixture to make it easier to pick up and move around.

#3 is the inside of the painted gutter. I actually spaced it out so that 2 of the screws holding the handles on double as mounting screws for the light - it's one of those deals where it has holes on the back that you slide the screw head into and then slide to lock - knowwhatimean??

#4 is the light snapped into place. I made end caps out of pieces of corrugated plastic painted with the same black krylon I used on the gutter just glued into place, with a hole in one side for the light strip cord. I didn't want light to bleed out the ends.