DIY UV Steralizer Ideas

Jimbo · 09-16-2004, 03:48 PM

I've been wanting to get a steralizer for my tank, but they are expensive. You can get 9watt standard UV bulbs for about $12 bucks. That should be good enough for my tank. Now I see no reason why we can't just submerse this bulb in a chamber of moving water as long as the base is sealed, they really don't get that warm. 9w should not add that much heat either. This should be more effective than haveing a quarts evelope. Of course you would need to clean the bulb now and then. But think the uv would kill anything that trys to grow on it.

This is my idea.

Some 3 or 4 inch PVC about the lenth of a 9w bulb
Screw in cap on one end and sealed cap on the other. You could probally fit two bulbs in this way.

Modify the screw in part to fit the bulb and silcon / epoxy the bulb in. Screw it into the chamber with thread tape.

Drill and tap top and bottom for water feed.

When the bulb burns out just buy another screw in piece and replace it.

You could just by a 9w watt spiral type bulb from local store and use the ballast that is in it to run the bulb, a couple of bucks

darthteddy · 09-16-2004, 06:22 PM

one thing is you have to get a quarts chamber or somethin. other wise it wont work
and that is expensive

Jimbo · 09-16-2004, 08:12 PM

Quote:

one thing is you have to get a quarts chamber or somethin. other wise it wont work
and that is expensive

Not if the bulb is in direct contact with the water, trying to avoid the quarts chamber, just seal the power end of the bulb really well, it would be sticking out the screw in module anyway.

Jimbo · 09-16-2004, 09:00 PM

Here's Pic of what I'm thinking, if you put the outlet spout low enough and the unit is high enough to gravity feed back into your sump or where ever you really woudn't need to seal the top either.

Geoff · 09-17-2004, 09:48 AM

i think the problem with doing it that way is the bulbs are prone to cracking when in contact with water. it would not be good if one were to crack, all kinds of fun with water and electricity.

i think this is a safety issue.

G~

Mafiaman · 09-17-2004, 02:04 PM

I may be wrong about this with the lamp you have, But most lamps have an operation temp. that is high. In order for the gases to get to the proper state of excitment you must reach that temp.

Putting a lamp in water would prevent this.

Jimbo · 09-20-2004, 12:52 AM

These lamps operate pretty cool, I've heard that if you run them in a freezer it will shorten there life, but my tank is 81'. A 9watt bulb really wouldn't put off much heat and if you keep the igniter portion above the water level it should still stay warm and just in case the bulb was to break for some reason you won't fry your tank, I think that would be the main concern here. It should trip your EFI even if it does.

They contain some mercury, but so do most bulbs we run above the tank. I see no reason for it to break though. They also generate a static charge and so you should definitly have a grounding probe (you should have one anyway)

. Actually that static charge should help your skimmer, if you put the sterilizer before it.

So the main concern here is bulb breakage, personally see no reason for it to break from being in contact with the water. How often have you seen a flourescent bulb shatter even from splash?

PaintGuru · 09-20-2004, 10:12 AM

I would just worry about the temperature gradient between the outside of the bulb (81F from your tank water) and the inside of the bulb (whatever temp the gases are at) causing the breakage of the bulb. Submersion is different then a splash.

Geoff · 09-20-2004, 12:14 PM

how are you going to control contact time?

just thinking out loud.

G~

Jimbo · 09-20-2004, 01:16 PM

Quote:

how are you going to control contact time?

just thinking out loud.

G~

Not sure what you mean. Spanky recommends 4x hour water movement. So for my tank that would be 200gph. With the bulb in direct contact with the water that should increase it's affectiveness at least 2x over an envelope method.

I will be ordering the bulb next month. Also concerned about bulb breakage, so will test the bulb with a bucket of water to see if it breaks or cracks. Can test voltage leakage at that time.

PaintGuru · 09-20-2004, 01:56 PM

Why would no envelope increase your effectiveness? Other then from a build up of dirt and stuff on the envelope?

Jimbo · 09-20-2004, 02:04 PM

The envelope would block some UV, although not sure how much, just guessing.

Jeremiah · 09-20-2004, 02:08 PM

Well for all the screwing around with this unit and then not even knowing how well it will work I would think it would be easier and probably more cost effective in the end to just buy one for $79... Then you know it's going to work and you won't have to make several attemps to get it just right. Just my $.02

Jimbo · 09-20-2004, 02:11 PM

Quote:

Well for all the screwing around with this unit and then not even knowing how well it will work I would think it would be easier and probably more cost effective in the end to just buy one for $79... Then you know it's going to work and you won't have to make several attemps to get it just right. Just my $.02

LOL, it's just the DIY'er in me.

Check out this link on UV envelopes and lights, there are cold cathode bulbs available but not sure where to get them though.

http://www.light-sources.com/germicidal1.html

Jeremiah · 09-20-2004, 02:14 PM

I used to like the idea of DIYing it, but after my first few projects i like to just buy stuff that works and I can just plug it in. Don't want to share my failed projects, lol

DIY UV Sterilizer Ideas