My new filter is the first one I've had with a UV component. I understand the bulb has to be replaced about every 6 months and is very expensive. I've read UV light will help algae but algae is beginning to grow on my old decorations again so I'm wondering how effective the light chamber really is with algae. If it's not so much I'll likely turn it off unless I have a bacterial bloom.
UV light?
- Thread starter jimwg
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The UV filter will do nothing for surface algae. That is due to an imbalance between light and nutrients. UV lights are only effective against floating unicellular algae which is typically not an issue for indoor tanks. If your tank was outdoors or exposed to uncontrolled sunlight this may be worthwhile but in general they have no value in tropical tanks.
Ryt, to reduce Nitrates. My levels remain around 20ppm but I'm still going to get some kind of live plants. I don't have any presently.
OK. Thanks for the info. I guess it's a waste of money to have purchased the option then not use it but I guess it's there if I ever actually need it.
I don't understand why you would want to get a UV light... is that what you've had all the time? Or are you looking into getting one?
If you want to keep it as a backup, that's OK. I would return it if you aren't going to use it.
UV can (or will) cause cancer so make sure you never have it on if you can see it. But it is not useful in freshwater tanks anyway. It can help with gree water, but that is easy to avoid by proper maintenance and stocking.
Problem algae is caused by a light/nutrient imbalance. The only way to deal with it is to establish (or restore) the balance. If you have live plants, this is needed. If there are no live plants, then it really doesn't matter.
NBitrates at 20 ppm is on the hgih side, is this occurring solely from within the tank? Or do you have nitrate in the tap water?
Problem algae is caused by a light/nutrient imbalance. The only way to deal with it is to establish (or restore) the balance. If you have live plants, this is needed. If there are no live plants, then it really doesn't matter.
NBitrates at 20 ppm is on the hgih side, is this occurring solely from within the tank? Or do you have nitrate in the tap water?
It is quite a bit more expensive than the next step down of the AquaTop line. Then again I do really like the intake and output valves that hang on the back of the tank and the media compartments are quite a bit bigger.
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I know, which is why the bulb is in a chamber invisible to the outside and blocked from the bio-media.
20ppm nitrates isn't at all on the high side, it's pretty normal for a well established tank. It's virtually impossible to get down to 0 nitrates unless it's a brand new tank that hasn't cycled yet. Yes there are some nitrates right out of our tap. Pig farms everywhere in Iowa.
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All fish are slowly weakened by nitrates. Ammonia and nitrite harm them (even kill them) rapidly, but nitrate takes longer but it is still toxic to all species. It can vary depending upon the level, the exposure time, and the species. But 20 ppm nitrate is as high as you ever should allow it, and if you can keep it well below this the fish will be healthier.
My tanks over 12 years have always beeen in the 0-5 ppm range. This is the API test so it might be 0 or 1 or 4 or 5, but no more. Planted tanks (low-tech or natural like mine) often have zero nitrates permanently.
It is easy enough to keep nitrates very low/zero if they only occur within the tank. Nitrates in the source water is a very different issue. If this is only around 5 ppm I would tend not to worry, but keeping the tank very low is more important.
On doing some more research I, as in days gone by, see a wide range of opinions regarding nitrates but I'm sure planted tanks are optimal for nitrate control. Previous to this tank set up I have now I for years kept just one large fish with gravel substrate and no plants (oscars and a jade goby) and my nitrate did register 20ppm in between water changes. Now I have 13 congo tetras and 2 kribensis in my 75 gallon with 141 biochem stars (long ran in other filters) in the AquaTop CF400UV filter I've been talking about with a large pre-sponge filter and the tank is bare bottomed (because I was orignally going to keep a bichir in it but decided on quitting the monster fish for awhile). I've been vacuuming about 5 gallons of water a day while sucking up the easily seen debris after the fish eat so every week I'm doing a 35 gallon water change (I get my water from a 50 gallon I pre-treat with Prime and even have heated to the same temp as my tank). I discovered my API nitrate and ammonia tests were more than a year and a half outdated so I tossed them and got new ones. My tank now registers as 0 ammonia and 5ppm nitrate (which is what it is out of the tap). I still am seeing surface brown algae even with the UV light on so everyone's right about it not being effective for that so I guess I'll leave it off unless I end up with some kind of bloom.
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Seems you are on the right track. I hope you are planning on a substrate for the tank with the Congos and kribs, this is crucial. The substrate is the biological base of any aquarium; the many species of bacteria that live only in the substrate are needed for the biological system to function properly and well. A tank should be able to operate without a filter, but never without a substrate.
Very true, on both points. Nitrates is a subject not well covered (by scientific study) until more recently. Over on the cichlid forum they now state that cichlids will deteriorate with nitrates at 20 ppm, and nitrates may be more of the reason behind hole in the head and Malawi bloat than previously understood. The minimal but recent scientific studies do indicate nitrates to be dangerous, and keeping them as close to zero as possible will improve fish health. I had a good discussion with Neale Monks on this, and when I asked just what nitrates did he responded that it is best to think of nitrate as a slow weakening of the fish, leaving it more susceptible to disease and various other things along the way that it would, were it not for the nitrates detriment, be able to easily deal with.
Plants do help, but not in the way some assume. Most aquatic plants do not readily take up nitrate. They prefer ammonium (ammonia) as their source of nitrogen, and faster growing species can assimilate a great deal. They out-compete the AOB (ammonia oxidizing bacteria) for ammonia, and this means less nitrite, and thus less nitrate. Plants only turn to nitratee if ammonium is insufficient in balance with the light intensity and other nutrients for photosynthesis.
I don't agree with this statement at all. Substrate collects not only good nitrifying bacteria but also pathogenic bacteria and the necessary vacuuming of it removes both. I've always relied on massive amounts of bio-media in my canisters so that the biological filter can grow undisturbed in the dark controlled environment.
Seems to me if I maintain 0 ammonia & nitrites in my tank plants would be forced to consume nitrates which the biological filter cannot.
No idea what you might mean by "if I maintain 0 ammonia," there is no way you can do this. The ammonia continually being produced by fish, the decomposition of organics in the substrate, and some bacteria will be taken up by the plants immediately. They are faster at this than the nitrifying AOB.
Plants will not take up nitrate unless the light is of sufficient intensity to drive photosynthesis past the level of available ammonia, and always assuming the other required nutrients are available as well. Studies show that plants will actually take up nitrite before nitrate. The reason is that plants must convert the nitrate back into ammonium and this takes additional energy which the plants will not spend unless forced into the situation. Dosing nitrate in high-tech planted tanks is done because there the ammonia is quickly insufficient and most would prefer dosing nitrate over ammonia/ammonium, though nitrate is detrimental to fish. But high-tech is another world.
You are free to disagree, but what I wrote earlier is still accurate. There are more bacteria and different species in the substrate than in any filter,no matter how many or how much media. And there are and need to be aerobic and anaerobic bacteria species. Bacteria in the substrate use nitrate to produce oxygen, and some of the nitrate turns to nitrogen gas and escapes in to the atmosphere. A healthy substrate is the foundation of a healthy aquarium.
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