There are several intake UV sterilizers you could look at
Downsides of UV sterilization?
I'm having a little bit of a hard time finding good information about UV sterilisation. It seems like everyone who writes about it is also selling it and I'm not finding a lot of detailed info or recommendations here. To me it seems like a real nice idea. Currently I'm trying to get the hang of growing plants in a high tech environment. I have my high powered lights, my DIY CO2, my ferts. The plants seems to be growing really well, but the water has turned green.
Now I actually don't worry about algae growing on the glass (easy to scrape off), on the gravel (it looks nice and feeds my otos and even platys), or on the plants (doesn't seem to be happening), but I don't like the stuff that just clouds the water. I wish I could keep everything as is, but with clear water. That's why I'm interested in a UV steriliser.
1) Is there any downside to having a UV steriliser, aside from the cost? Is there some harm associated with killing free-floating bacteria, for example?
2) Are there any UV sterilisers appropriate for a 20 gal? It seems like everything I find is for a pond or a large aquarium, and I'd hate to get something larger than needed. It seems to me like I'd need something pretty small. (edit: What wattage/flow rate would be appropriate for just green water control in a tank this size?)
Now I actually don't worry about algae growing on the glass (easy to scrape off), on the gravel (it looks nice and feeds my otos and even platys), or on the plants (doesn't seem to be happening), but I don't like the stuff that just clouds the water. I wish I could keep everything as is, but with clear water. That's why I'm interested in a UV steriliser.
1) Is there any downside to having a UV steriliser, aside from the cost? Is there some harm associated with killing free-floating bacteria, for example?
2) Are there any UV sterilisers appropriate for a 20 gal? It seems like everything I find is for a pond or a large aquarium, and I'd hate to get something larger than needed. It seems to me like I'd need something pretty small. (edit: What wattage/flow rate would be appropriate for just green water control in a tank this size?)
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Most of the nonsense about UV comes from people who never used it. Or used it but never tested or verified anything. Same as a lot of life.
In my opinion, The single best source of readily understandable info is the book "Aquatic Systems Engineering" by P.R. Escobal. ISBN 1-888381-05-1 It's a bit expensive, but you may be able to borrow it from your library or via inter library loan. I just happen to have it open on my desk right now. ;-)
Amazon lists it.
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias=aps&field-keywords=1-888381-05-1&x=15&y=15
The key question is what do you want to kill? Different organisms take different dose exposures to kill. Achieving the correct kill dose depends on flow rate, exposure time, and total water changes per day. Just connecting a UV unit in line with a canister filter is pretty useless because the water is moving too fast to kill much of anything.
For instance, at a flow rate of 100 gallons per hour it takes just under 2 hours for for one complete change of water on a 20 gallon tank. At that flow rate a kill dose for most bacteria, algae and fungi would require a 3 inch 25 watt sterilizer.
In my opinion, The single best source of readily understandable info is the book "Aquatic Systems Engineering" by P.R. Escobal. ISBN 1-888381-05-1 It's a bit expensive, but you may be able to borrow it from your library or via inter library loan. I just happen to have it open on my desk right now. ;-)
Amazon lists it.
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias=aps&field-keywords=1-888381-05-1&x=15&y=15
The key question is what do you want to kill? Different organisms take different dose exposures to kill. Achieving the correct kill dose depends on flow rate, exposure time, and total water changes per day. Just connecting a UV unit in line with a canister filter is pretty useless because the water is moving too fast to kill much of anything.
For instance, at a flow rate of 100 gallons per hour it takes just under 2 hours for for one complete change of water on a 20 gallon tank. At that flow rate a kill dose for most bacteria, algae and fungi would require a 3 inch 25 watt sterilizer.
Sigh....:icon_cry: If you only knew the frustration I've been going through trying to grow green waterborne algae.
Hmm. I might have to find out more about the steriliser I was considering. It's 9 watts, 9 inches (exterior length). I thought I'd hook it up to a 350 gph powerhead. It says the max flow rate is 900 gph, but maybe that doesn't correspond to an adequate kill time for algae? Actually can we know if that's long enough without knowing the interior diameter? I guess I could always reroute some of the powerhead water so it would go through slower.For instance, at a flow rate of 100 gallons per hour it takes just under 2 hours for for one complete change of water on a 20 gallon tank. At that flow rate a kill dose for most bacteria, algae and fungi would require a 3 inch 25 watt sterilizer.
I'll have to find that book and do some calculations. Basically I just want the cheapest UV steriliser possible, but I'd prefer one that didn't reside inside the aquarium and take up a lot of space.
My recipe is 1 part bright light, 2 parts decaying leaves of anacharis (they are alive and growing, but the original leaves from the store melted), 1 part DIY CO2, 1 part FloraPride. And a dash of new tank syndrome.Sigh....:icon_cry: If you only knew the frustration I've been going through trying to grow green waterborne algae.
I'll trade you a sample of my water you can use to seed your culture if you will send me some of whatever kills it.
I've seriously thought about routing water through a container filled with daphnia in a net of some kind, but I don't know enough about it to know if that would work, much less where to obtain live daphnia. At least I know where UV rays come from. Kind of.
Get the UV sterilizer. You won't regret it for green water. I wouldn't worry to much about flow ratesor contact time, green water is easy to kill. A day or two with it running and your green water will be gone. Only thing is after the green water is gone you may not ever need it again.
There is really no downside to using a UV. If the flow is correct it will keep your water crystal clean and kill parasites at the same time. If you have GW don't stress and try to find the 'balance' just get the UV and enjoy your tank. In addtion, I remember without a UV my acclimation of cardinal tetras was about 50%, with a UV it went up to about 90%, since the UV killed parasites that would attack them while their immune system was compromised during stressful acclimation.
Sharkfood, I went through the same problem with GW when I set up my tank. The UV sterilizer did the trick for sure. I used a cheapo green killing machine from Petsmart and it worked fantastic. I used it for a week and removed and I havent ever had to use it again.
My point, buy cheap if its just for green water.
My point, buy cheap if its just for green water.
the only downside to using U.V. sterilizers are really the cost, and the effect of having one more piece of equipment in/on your tank.
once you get them dialed in they are great for what they are for. the biggest mistake most people make is having the flow rate to high. and they get discouraged when the results aren't instantaneous.
if you get one and put a ball valve in to set the flow rate put it after the pump but BEFORE the UV unit, that's extremely important, I have seen more than once people trash a UV unit because they put a valve on the outflow which over pressurizes the unit and causes either an external leak or an internal leak and short.
once you get them dialed in they are great for what they are for. the biggest mistake most people make is having the flow rate to high. and they get discouraged when the results aren't instantaneous.
if you get one and put a ball valve in to set the flow rate put it after the pump but BEFORE the UV unit, that's extremely important, I have seen more than once people trash a UV unit because they put a valve on the outflow which over pressurizes the unit and causes either an external leak or an internal leak and short.
anyone got a link for a uv sterilizer for a 20g? ive got a parasite killing certain fish and, my chemical treating options are limited due to my inverts
bigboij, the green killing machine was mentioned in one of the above posts. You can find it at petsmart and amazon. I like that it has its own pump so you don't have to mess with that. The downside I see is that the whole unit sits inside your tank. It seems like it could look a little large in a 20 gal.
^^ wouldn't i be able to use it for a few days to clear any parasites and be good from then on or would it have to stay in use all the time?
Oh, interesting... I have one of those in the tank UVs. It works pretty well with diatoms.Just connecting a UV unit in line with a canister filter is pretty useless because the water is moving too fast to kill much of anything.
For instance, at a flow rate of 100 gallons per hour it takes just under 2 hours for for one complete change of water on a 20 gallon tank. At that flow rate a kill dose for most bacteria, algae and fungi would require a 3 inch 25 watt sterilizer.
Continuing with the "downsides of UV" question, I read in a couple of places that UV sterilisation will oxidise some of the nutrients you feed your plants. Does anyone know what nutrients are affected? How should one adjust the fertilisation for a tank that has at least periodic UV sterilisation?
Supposedly iron but there's no proof that it affects the plants.Continuing with the "downsides of UV" question, I read in a couple of places that UV sterilisation will oxidise some of the nutrients you feed your plants. Does anyone know what nutrients are affected? How should one adjust the fertilisation for a tank that has at least periodic UV sterilisation?
Sometimes, I turn on my UV lamp at night.
I'm assuming plants aren't conducting photosynthesis at night, so nutrient uptake is minimal.
IF the UV sterilizer removed or at least oxidized the nutrients, I would consider it kind of like a water change.
Since I don't want to overload nutrients in my tank, I guess the UV would remove excessive amounts at night. No chance for algae to take advantage of the nutrient imbalance.
Whenever I wake up in the morning, I unplug the UV sterilizer (if I had it on) and then dose my nutrients before the light turns on.
That's just me.
I'm assuming plants aren't conducting photosynthesis at night, so nutrient uptake is minimal.
IF the UV sterilizer removed or at least oxidized the nutrients, I would consider it kind of like a water change.
Since I don't want to overload nutrients in my tank, I guess the UV would remove excessive amounts at night. No chance for algae to take advantage of the nutrient imbalance.
Whenever I wake up in the morning, I unplug the UV sterilizer (if I had it on) and then dose my nutrients before the light turns on.
That's just me.
I would Not flow much beyond 200gph .......... even less flowrate!! reduce reduce reduce ....... you can reduce the out-let ....... NOT the inlet !Hmm. I might have to find out more about the steriliser I was considering. It's 9 watts, 9 inches (exterior length). I thought I'd hook it up to a 350 gph powerhead. It says the max flow rate is 900 gph, but maybe that doesn't correspond to an adequate kill time for algae? Actually can we know if that's long enough without knowing the interior diameter? I guess I could always reroute some of the powerhead water so it would go through slower.
I'll have to find that book and do some calculations. Basically I just want the cheapest UV steriliser possible, but I'd prefer one that didn't reside inside the aquarium and take up a lot of space.
:fish::fish::fish::fish::fish::fish:
Check-out Don's book/link ............. contact time is the key ! Meaning..... water has to get full effect from the bulb....... BULB/Lamp needs to be clean inside the unit , also !!
Not to get too much off topic, but why does it matter whether we reduce the inlet or outlet? Both ways seem to have the same effect, don't they?I would Not flow much beyond 200gph .......... even less flowrate!! reduce reduce reduce ....... you can reduce the out-let ....... NOT the inlet !
Reducing the inlet put serious strain on the pump which can burn it up.
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