UV Sterilizers - Which One?

[NaH2O]

So, I've been trying to determine what type of UV Sterilizer to get for my system. I'm getting confused on figuring out what Watt I need. According to this link: UV Sterilization Overview - I would need a 40 Watt Sterilizer. I guesstimate my water volume to be around 150-160 gallons.

Wattage / Tank Gallons

8-9 Watts / up to 55 gallons
15 Watts / 55-100 gallons
25-36 Watts / 100-150 gallons
40 Watts / 150-250 gallons

I'm confused because different brands have different recommendations. So, do I truely need a 40 Watt unit, if the manufacturer says I only need a 25 Watt one? Any recommendations to help me understand what I am looking for in a good unit, or how I can narrow my choices down? Does the water flowing in a spiral path around the bulb (Corallife Turbo Twist) make a difference compared to regular flow?

Pentair Aquatics/Rainbow Lifeguard - ease of bulb change

Corallife Turbo Twist 18W or Corallife Turbo Twist 36W

Now according to Aqua UV Sizing Chart I require the 40W. AquaUV Sterilizer - these come with a wiper.

Same as above - different vendor - Aqua UV Sterilizer - but here, what difference does the 3/4" unit have compared to the 2" unit?

According to this brand, I only require a 15W unit - Current USA Gamma 15W

Sorry for all the links, but it was the only way for me to show what I was talking about.

TIA

 

[spooda420]

Nikki,

I have 2 Tetra UV 2's on my system I have a 120g display tank, 100g sump, and a 30g 'fuge. If my memory serves me correct they are 18w each. I have not had any problem with pathogens or HA as of late. I attribute that to the UVs.

In this hobby more is better right? The bulb changes for my model is pretty easy. Hopefully others will join in.

 

[Ed Hahn]

Nikki,
I am assuming the Aqua UV 2 inch model has more contact time than 3/4 inch because of diameter. I like the pin design on the end for bulb replacement. The bulb is stated to last 14 months. That 14 months is kinda pushing it I think. The wiper leaked once on me. I went and bought a sink washer(rubber gromet) and replaced it. It works like a champ. I feel the wiper could be a weakness. If you move it too much it could leak again possibly. Mine is working good for now. I can move it and it will not leak. But thats just a heads up it could happen again. My oppinion is that the Aqua UV is the best UV I have owned.
Mine is sitting as we speak. I do not want to get rid of it. If you were closer I would let you borrow it to try it out. Maybe I can take a picture and show you the bulb and UV so you have more of a idea how Aqua UV looks and how hard it is to replace bulb.
I thought it was quite easy compared to my old Marine Tropics UV.
.....let me know if you want pix. I can send pictures. I just can not post em yet...lol. That may be a good thing for people on here..
Merry X mas Nikki,
Ed

 

[Boomer]

Nikki

Get the book from my old friend Pete Escobal :Aquatic Systems Engineering, this will explain in great detail how to choose the proper UV. The book also has all kinds of stuff that will be of great interest to you . The stuff on that Overview page is so much giberish. You need to know wattage, zap rate and actual flow rate, as in gals /min, dia of unit, tubing etc..


http://www.amazon.com/gp/reader/1888381108/ref=sib_dp_pt/103-0371073-1435045#reader-link

 

[fishermann]

Nikki I just bought a Aqua UV for my new 225 after talking to Ed Hahn and calling the co. and talking to some guy there. The only difference in the 3/4 verses the 2" is the inlet and outlet. They both have the same bodies and the 3/4" has the 2" ports but they have glued reducers inthem and send the 3/4 barb fittings to screw in. The 2" is an option on the bigger watt ones incase you want to plumb it into 1 1/2" pvc hard pipe or smaller. The 2" reducers they glue in are for 3/4" threaded barb fittings and would be hard to plumb in to pvc pipe if you follow me. I have ran UV for 20 yrs and swear by it and I believe Aqua rateing is more in line with what is needed on a salt water aquar. verses a freshwater setup which is what the others are rating at but don't tell you. I also ordered the wiper option, hope it works and it looks like it sell be really easy to change bulbs. The fellow also said theres are desighned to work with a high flow system. Also the 40 watt one is 43" long and with the wipr option you well need that much room to pull the wiper rod out beyond the Uv's 43" if you follow me, that is another reason I went with the 57 watt the body is fatter and the bulb the man said is a more intense bulb besides the watt diff. so it kill the same with less length. The 25 and the 57 are both only 26 1/4" long I believe, Marine Depot has the lengths listed. Hope this helps.

 

[spooda420]

The information I orginally obtained several years ago was the most impostant properties are that it is a high enough wattage and a slow enough flow rate kill pathogens.

So a lower wattage UV with a VERY slow flow rate is sometimes better than a high wattage fast flow rate. Is that correct?

 

[Ed Hahn]

The information I orginally obtained several years ago was the most impostant properties are that it is a high enough wattage and a slow enough flow rate kill pathogens.

So a lower wattage UV with a VERY slow flow rate is sometimes better than a high wattage fast flow rate. Is that correct?

The more contact time the more effient your UV works usually.

 

[fishermann]

I asked that very question to the guy at Aqua and his answer was to flow theirs at the rate they suggest which I thought was high but he said theirs well have a good kill rate at the suggested rate and they do have a slight variance in the rate. He said not to flow it to slow or you won't get the turm over rate neccessary to keep up with the size of the tank.

 

[Ed Hahn]

John,
My UV is rated up to 1200 gallons per hour. That just does not sound real to me. I only have a 25 watt UV.

http://www.customaquatic.com/customaquatic/subsubcategorypage.asp?subcatindexid=uv-aq-sw My UV is the 25 watt with 2 inch outlets.

 

[fishermann]

I know what your saying and I have always thought that way but I asked this guy that and he said that with the quartz sleeve and the bulbs they use that they well do as claimed. I think on the 57 he recommended a 9.5 mag pump for the low rate and I told him I had a mag 7 from the past and he said to get a 9.5 so I ordered one with the uv.

 

[dgasmd]

Nikki:

I think what your ultimate use for the UV sterilizer is will dictate what wattage you will require for a particular system. I personally use them for a couple of things:

Free floating algae
Fish pathogens

For the first, you really don't require much. For the second, you do. I had a very small UV unit before for my previous tank, but I am stepping it up considerably this time around. After fiddling with the Pentair units, I think I will actually get an Aqua UV unit instead for a couple of reasons. Even though they may be more expensive for the same wattage if you compare it to the pentair units, you could get a single bulb unit. That in itself over time will pay for the difference in bulb replacents. The other reason in that it is much easier to place in tight places and still get to it.

I personally plan to plumb it so it is before the skimmer. It may really be a mute point, but for location it will work for me too.

 

[NaH2O]

Thanks everyone! I ordered the Aqua UV 40 watt unit with the wiper upgrade. Now the question is, I have a Mag 12 return, so I could just plumb it on the return to the tank. Do you think that flow may be too fast? (I would like to get Fish Pathogens, too) I have a Mag 9 around here somewhere, so that is an option, too.

 

[fishermann]

Nikki The longer the contact time the better, I would run it at the lower end of the suggested flow rate. If you run it on your return, I think you well be slowing down your return flow also with the extra bends and added plumbing. Even if you T off of the return you well have to figure out the flow through the unit you are getting. I would run it at the lower end of the suggested rate and on its own pump.

 

[Ed Hahn]

Nikki The longer the contact time the better, I would run it at the lower end of the suggested flow rate. If you run it on your return, I think you well be slowing down your return flow also with the extra bends and added plumbing. Even if you T off of the return you well have to figure out the flow through the unit you are getting. I would run it at the lower end of the suggested rate and on its own pump.

I agree with above Idea, very good idea. You could also just plumb it into your sump with smaller pump and turn it on when you want. If you plumb it into your sump you could see if it raises your temp and try either pumps and compare your heat or if it does produce heat. You could plug it in when needed if plumbed separately.
Good Luck Nikki
Ed

 

[tdksound2005]

hi guys , i hear everyone going on about uv,s is it really nesserary to have one .
i have a 150 gallon fowlr set up for 3 years now and no problems.i even have a powder blue.no problems. save your money and take your girl out for a nice meal.
or buy more fish,lol.