Good UV Steriliezer

[tony098]

What is the best UV for less than $200? Thanks.

[XtrmCHoPZ]

What wattage?? what size tank.

[tony098]

125 gallon. What wattage do you recommand?

[XtrmCHoPZ]

I would say 36 or 40, I have a 40 on my 125. Some might say less but I think less wouldnt even do much. I use a Gamma, its ok but i had problems setting it up, sleeves kept cracking.

[rickburdeniuk]

<a href=showthread.php?s=&postid=7322580#post7322580 target=_blank>Originally posted</a> by tony098
125 gallon. What wattage do you recommand?
Wattage is even less useful in UV then it is in lighting, what you need to know in the case of UV is the exposure rate. Then to compare brands you need to know if they are quoting exposure rate and the end of the bulbs life or beginning, and of course how long a bulb lasts.

To determine your target exposure rate we'll need to know how fast the water will be flowing though the UV and what your trying to accomplish (kill aglae/bacteria and clean water, or blast parasites). Let me know some of that info and I'll give you a more specific recommendation!

I almost bought the 40W Gamma for my 120 as well, but in the end went with Emperor Aquatics 40W unit. Emperor Aquatics is the best IMHO, followed by AquaUV, and then come the typical hobbyist brands, of which on paper Current USA's Gamma units looked the best when I checked them out.

Not all are appropriate but don't overlook some pond supply places as a source as well:
http://www.hagen.com/usa/ponds/sub_category.cfm?CAT=30&SUBCAT=3014

[tony098]

My priority is like this: reduce disease (parasites/ich) > aglae > clean water.

I think I need a pump to push water thru the UV, right? I have a spare maxijet 1200 but I can purchase another pump if neccesary. Thanks.

[XtrmCHoPZ]

i think maxijet1200's are 295 gph, thats too much to control disease.

[rickburdeniuk]

Yup - parasites are the hardest to work on.

To achieve most UV benefits you need a one pass exposure around the 15,000, µw/cm² and for the tougher undesirable algae blooms bacteria I've heard reports of 30,000; most hobbyist companies’ quote GPH based on a number in this general range while the most aggressive industry standard puts the number at 22,000.

However in the case of odinium ocellatum (ich) parasite the lowest number I've seen is 35,000, while I've seen reports of cryptocaryon irritans (ich) requiring 800,000!!! Perhaps the difference is accurate or perhaps one measure actual extermination, while other measure sterilization. Generally speaking though I believe the accepted parasite sterilization standard is 90,000 to 100,000 combined with a 5-6 times turnover in our tanks to affect a majority of applicable parasites. Turnover is however based on actual water volume, not the potential size of your tank.

If you know the specific parasite you want to kill you have to figure out it's lifecycle (how long it lives), from this you develop your turnover rate (how much do I have to turnover to kill 99.9% of it).

Take a look at one of these sizing charts:
http://www.aquaultraviolet.com/uvsizingchart.php
http://emperoraquatics.com/aquasmartuv.php

For comparisons sake The Aqua UV Classic 57W unit is $305 from premimaquatics.com (http://www.premiumaquatics.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=Aquauv) (a sponsor). It claims 90,000 µw/cm² at 1066 GPH *after* 14 months of bulb use, so that GPH is good enough for up to about 180 gallons of water.

Now if you have say 100 gallons of actual water it requires a GPH of 600, so my single pass dosage is a whopping 160,000 (GPH*exposure/your GPH). I find this a very comfortable 50% above any itch sterilization number I've ever seen, but well below actually blowing animals (like some grown up parasites). One benefit of oversize your system is you don't have to change lamps as quickly, a 57W lamp at 70% life is still 50% more the my minimum for example - thus I can perhaps run it for up to 18 months with some degree of comfort.

All reported problems aside the CurrentUSA gamma 40W UV unit is listed at $180 sounds like a great deal.... it puts out 30,000 at 2880gph at the beginning of it's life. At 12 months the bulb is down to 60% of it's original output (I emailed them), so if you want to be killing parasites at the 12 month mark you have to adjust... and the magic number for the same 100 gallon example is... 576GPH.

At $200 you can afford an AquaUV 25W system, just use the charts to figure out if it's right for you (about 400GPH@90,000&14 months). Replacement lamps are about the same price for both manufactures, something around $50 so you figure all quality issues aside to make up the price difference your cost benefit on the Aqua UV 57W vs. Gamma 40W unit kicks in at year five.

I went with an used Emperor Aquatics unit because I think they are better; problem is they are much much more expensive. You can find their marketing info off the second chart I liked to above and I recomend reading it if your really interested as it has some good info. Things like how competitors measure output assuming you have perfectly clear water.

Thus, the last thing I'll say is many people recommend running some kind of filter before the UV to ensure it's working at max efficiency so take that 576GPH number I mentioned with a lot of scepticism. As far as I know every number above assume perfectly clear water which we won't have, especially wihtout a fancy mech/chem filter before it.

I used these threads to compose the above, credit due to those authors:
http://www.reefcentral.com/forums/showthread.php?s=&threadid=423026&highlight=orthophosphates+uv
http://www.reefcentral.com/forums/showthread.php?s=&threadid=360060&perpage=25&highlight=orthophosphates%20uv&pagenumber=1
http://reefcentral.com/forums/showthread.php?s=&threadid=321032&highlight=UV
http://aquariumpros.ca/forums/showthread.php?t=18024&page=2&highlight=gamma

I hope all the linking is within the rules, apologies if not.