[dwalstad]

I've been using the 7 watt Submariner in my 45 gal for several months now. Last week I purchased 2 more Submariners for the other two tanks (a 50 gal and 55 gal). I decided that the fish that survived the MB outbreak in 2004/2005 are probably chronic carriers of the disease. A few have died since then. Why push my luck? I love my fish and the Submariners are cheap and will truly protect them from constant re-infection. It will also block disease transmission to uninfected fish.

The Submariner works fine for water movement in the tank. And because NPTs don't really need biological filtration, it doesn't matter how efficient the filter is for biological filtration.

Mommyeireanne, I too have got a few drops of water in the quartz sleeve, but I don't see how that would hurt the UV light and its sterilizing effect.

Now folks, here's some hard science that you all need to know, especially if you don't want to run the UV filters 24/7. UV light kills bacteria (and the cysts of many pathogenic protozoa) by messing up their DNA (specifically, creating thymine dimeres in the DNA). However, bacteria can repair the damaged DNA. One major repair mechanism that bacteria use to repair DNA damage requires light.

Bottom line: your UV sterilizing filter will kill more bacteria and protozoa if you run it at night.

Also, I would add that water movement is going to help fish more at night. That's because at night the plants aren't photosynthesizing and producing oxygen.

Running UV sterilizing filters at night keeps the water oxygenated when oxygen is needed most and is more effective in killing potential pathogens.

 

[dwalstad]

I have not had a problem with water leakage in mine. you might try a little Vaseline on the O rings when you put it back together.

Thanks for the tip. I hadn't thought of that, but it makes perfect sense. One should never underestimate an O-ring!

 

[dwalstad]

I got one more question for you guys. My biggest tank is 20gallon right now but I am planning to get something bigger. So I want to be able to use the sterilizer in small and my future large tank. Looking at the submariner brand they have the 5 and 7 watt but both are rated at 132 gph??? What the healll?
It the same amount of water flow rate in and out why bother with 7 watt? The 5 watt should be effective within it's spec so seems to me the extra 2 watt is useless unless the gph can go higher for the 7 watt.

5 Watt 132 gph 9" x 3" x 2-1/2" 40 gal $65
7 Watt 132 gph 10" x 3" x 2-1/2" 70 gal $80

The water flow-rate for my 7 watt doesn't seem that fast in my 50 gal. Since you are considering a larger tank than the 20 gal, the 7 watt doesn't seem unreasonable to me. You can count on one thing, the more UV light, the more kill of potential pathogens, green water algae, etc.

 

[dwalstad]

Thanks Diana. I agree the higher wattage the more potent. The thing I question is that if the 5 watt kills 99% of the water that goes through the sterilizer at it's max rate and the 7 watt also have the same max rate than it would not be much different at al. But after a little more reading, it seems that the submariner have variable rate you can control so that I am guessing at lower flow rate it would be 99% but as the flow rate increase the potency decreases and that would justify the 7 watt usage because it will be more effective at higher flow rate.

Sounds reasonable.