MH minimum temp?

[JoshF]

Well, my new propogation set-up is in an uninsulated, unheated garage in Seattle. This means that the temp gets to a maximum of 43 degrees on many days. My 400W MH pendant will NOT fire outdoors, or within 10 minutes of coming indoors. After warming up, it fires fine. Now, obviously AFTER it's going, a low temperature is NOT a problem. I'm assuming the gas in the bulb needs to burn at a certain temperature and not the ballast that is too cool. I imagine putting a small heater in the pendant or near the pendant that would come on for a half hour before the light came on would do the trick, but I have never seen a small heater like this. I want something essentially like a muffin fan, but with a heating coil. Will this work or is there a better way?
Josh

 

[reefhound]

Hello josh, what do you hope to grow in 43 water?
i think you need to rethink where you will keep you tank.i im keeping mine indoors but with a bit of fuss from the miss's. 4 tanks is her limit!
this is no flame but please move you tank inside if there is anything in it!

 

[JoshF]

ummm, the OUTSIDE temperature is 43 degrees... My water temperature hovers steadily around 78 degrees. I'm not precisely a newbie by any stretch of the imagination, but being new to the Northwest and having a unique tank location presents problems that I didn't have while living in the Napa Valley in California. Besides, there are plenty of fascinating creatures that live in water that cold. Tropical organisms aren't the only interesting ones in the world. In fact, I live a quarter mile from a waterway that is very cold and boasts a diversity equally as great and beautiful as any tropical reef (as long as it's not spring or summer...)

I'm glad you didn't mean it as a flame, and were only trying to keep future generations of clownfish and corals from having to wear fleece. However, I wasn't asking about how to be a hobbyist in cold weather. If there is any ambiguity about what I am asking; please let me know. However, all I am asking for is help adding on to a MH pendant so that IT will fire in 43 degree temperatures.

Anyone?

Josh

 

[914]

perhaps....

(and this is just an off-the-cuff idea)

you could tent the tank and it's pendant.

what i mean is, use a material (there are modern plastics that would work for this, but i have no idea where you'd get some) that can take the heat of the MH pendant and form a sort of teepee around the pendant that goes down to the top edge of the container. this might trap enough heat (off of the water) to allow the MH to fire. obviously the material need not actually touch the pendant, but could be knotted a bit higher on the pendant's cord.

the drawbacks would be:
1) a fair amount of moisture trapped in the apex of the teepee, right around your pendant. possible corrosion problems.
2) might not be warm enough.
3) MH could get too hot for whatever material you're using

taking this one step further, you might instead use foam-core insulation panels to construct a sort of hood over the container (or containers, maybe even go so far as to create a small 'room' out of it). this stuff i *have* used, and it's cheap and easy to work with. you can cut it with a utility knife, and duct tape works very well.

with a little experimentation you could pretty easily make something that'd cover the whole tank structure, light and all, and have a 'door' with duct tape hinges.

this might cut down on your overall heating costs for the water too. (i'm guessing you don't already have the tubs/whatever sitting directly on the cold concrete..)


going yet another step forward...

your best bet might be to insulate the garage space itself. roll batting (R-15?) insulation for 2x4 studs is about $12 a roll, and you shouldn't need more than 3 or 4 rolls to insulate the garage.

then, get an electric-powered kerosene heater.

the kind that look (and sound) like a miniature jet engine.

there are modern (read: expensive) ones that use piezio ignition and all that which can be used with a thermostat or a timer. they're pretty efficient, and if the garage isn't huge they'll heat the whole thing up *really* fast.

as for putting heaters directly on the pendants..

maybe you could use gutter-heating cable, wound around the inside (or outside?) of the pendant, but i'd be very careful about how much heat (from the MH when running) the jacket of the heating cable can take.

perhaps something as simple as an infrared (the kind for herps) or even regular lightbulb (60watt? 25 watt?) stuck inside the pendant next to the MH bulb would work. this would at least have the advantage of complete non-flammibility.. the worst disaster possible would be exploded bulbs with the remote possibility of a short/breaker trip.

hm.

this in an interesting question...

let us know what you come up with!

 

[JoshF]

914 and esmithiii:

I definitely like the heating lamp idea. The set-up is fairly temporary (less than 6 months) and will be used primarily for scale up. I have a ten gallon right now, which will seed a 50 gallon to be used for growing out seed clams. When I buy a house within the next year I will use the 50 gallon to seed multiple 300 gallon tubs. For this reason, the heat lamp is the best option for the short term. In the long run, insulation and a temperature and humidity control system will be used which will alleviate most of my problems.

Thanks for the ideas!

Josh

 

[esmithiii]

Um, those last two posts missed the point I think. I think you might rig a small space heater to come on as you described an hour or so before the MH lamps and then off 5 minutes after they fire. Another option might be a simple hair dryer vented in your pendant? You might want to convert the pendant to a hood design to facilitate this.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote

perhaps something as simple as an infrared (the kind for herps) or even regular lightbulb (60watt? 25 watt?) stuck inside the pendant next to the MH bulb would work. this would at least have the advantage of complete non-flammibility

He might be on to something here. Maybe not inside the pendant, but outside aimed at the pendant, or below it aiming up inside the pendant.

I am struggling with a similar issue... My RO/DI unit is in the garage and now that the temps have dropped, the water in the plastic lines are freezing. I run a small space heater in there to raise the temp just a little bit.

E