lduncan

Just because you've used one doesn't mean you know what it's doing and how it works. I don't have to physically use one to know how it works. The precision of the meters is only 0.01mg/L, with an accuracy of +/- 0.04mg/L. You can get similar accuracy from a salifert test. I guess because you're using an electronic device, it makes it "feel" more scientific and accurate. Layton

no, never tried one personally, but the reaction is the same, and photo diodes can be fooled by contamination and turbidity quite easily. I don't think they are worth relying on as a more accurate method. Just a guide. Hobby test kits can't tell you how good your phosphate is, just how bad it is. I don't take a undetectable readings as meaning phosphate is low, it just means it's not at eutrophic levels. Layton

Yip. I've got a few large soft corals in the tank, so it splits the aromatic rings in the terpine toxins they release, making them available to bacteria. The UV just makes DOC's smaller so bacteria can use them much easier, then the bacteria are removed through skimming. Better method than using carbon to me. Layton

You say that like the Hanna kit is actually any more useful Don't clean the glass that often, two or three weeks usually. It gets corraline on which is more annoying than any other sort of algae. Also depends on whether I keep up with syphoning, as my flow isn't really up to keeping all the detritus it needs to in suspension to get to the skimmer. The UV provides additional food for the bacteria which perform denitrification (and any other bacteria that want's it), by splitting larger organics. It's these bacteria which are responsible for storing phosphate in sand beds, and are the ones which purge phosphate out of rock (the cooking/shedding process). So yes, it will help with phosphate I guess by the fact that denitrifaction and phosphate go hand in hand. The bacteria try to saturate themselves with phosphate. They absorb much more than they need to live and reproduce, so if you can get them to the skimmer (usually in the form of detritus) then you're removing phosphate. Layton

My ortho-phosphate is undetectable, has been for virtually all the tanks life, except for about a month ago, when I detected a faint blue colour on the test for a couple of weeks. Nitrates were just over 5 the day I added the UV. Detritus is a good indication of bioload, and bacterial activity. Layton

I blew out the rocks today, and there was a significant increase in detritus come off them. That's a sure sign that de-nitrification has kicked up a gear. I'll measure nitrates at the end of the week and see if it has had any effect yet. Judging by what is coming from the rocks, I would think it has. Layton

Were not talking theories here. Where talking researchers who observe something and then find out how and why it happens. IE they have observations, some experimental results or measurements and they link the two. They then publish these papers in journals for review by others in their field. (Don't get me started on the Bubble Bee thing, do a bit of searching and find out the history on that one!) Physics is often a different kettle of fish, there are a LOT of theories floating around in order to explain various observations, many of them are yet to be verified by experimentation and results. Exactly it is a joke! You don't have to be qualified to know about a particular thing, and just because you are qualified it doesn't automatically make you right! It's when you have many independent people all involved in the same field saying the same thing, not one contradicting, that you have to say it's highly probable that what they are saying is accurate. I qualified that in terms of environments, and effects of sand bed cycling. It wasn't a stand alone statement. The fact that you think all the research, observations, and results are wrong, doesn't make it nonsense at all. Layton

Peer reviewed papers from many different sources highly increases the probability that something is accurate. Your definition of proof, and a scientists definition of proof are clearly two different things. Well if you keep finding screeds of information published and reviewed by people who know what they are talking about, which contradict what someone has said, and nothing supporting it, it's kind of hard to argue with that. Would you trust a scientist who spends their day in a coral research facility. How someone with TWO relevant PhD's, and over 50 years experience in the hobby, who has also spent many a day researching reefs and related environments? If people were limited by their own personal experiences, then there would be an awful lot of dumb people around. I have yet to be involved in a car crash. I don't have to experience one personally to realise that I don't want to be involved in one. Having said that, a lot of what I say and reccomend, I have also observed in my own tank, consistent with all the papers and apparently "irrelevant" scientific research. Sure is, and there is a lot of pure rubbish out there.Through university I have access to a number of various peer reviewed scientific paper repositories. It seems people are far to dismissive of valid scientific research on this forum. They think it's all theories, and stuff which doesn't apply when moved into tanks. Which is far from reality. This research is virtually all PRACTICAL. Layton

I haven't told anyone to follow a method blindly. Exactly the opposite actually. Mutations are occurring in nature all the time. UV from the sun causes mutations everyday. It's an everyday process. Also a significant percentage of mutations cause no permanent effects for two reasons: DNA repair - a cellular process which is used to try and protect the genome somatic mutations - which result in cell death. UV sterilisers kill (or severely injure) water borne bacteria, and promotes other biofilm based bacteria, which are more useful in your tank. I know how UV works and what it does. I considered ozone, and decide against it. Layton

Never posted bombers tank to prove any point. A photo proves very little. I did however post a picture of Eric's tank as an EXAMPLE (not proof) of what sand beds can do. (A point missed on some people who thought I was passing it off as my own tank :roll: ) Someone even picked up on the fact that it ran a DSB even though the picture didn't include the bottom of the tank. I try and provide info which is accurate, I don't necessarily try and prove anything. Nor do I ask people to prove anything to me. Give me an argument which is convincing and i'll go find the proof for myself. It's when in searching for info you can confirm it, or find out what really goes on. I don't rely on any one person for info, there is too much crap flying around to do that. It's when multiple qualified independent people confim something, that you know you can most likely trust it. I like Casinos too. Trams probably not so much. Layton

The fact that there are bubbles in there makes me think it's algae, plus it looks slimy not really the texture of a sponge. Keep skimming and the tank free of detritus, it will clear, but could take some time.

Dunno what's worse aiptasia or the zoas

No, I've said that sometimes you don't comprehend what you read, and some theories are stupid. I've never called you stupid at all. You ASSUME I haven't posted pictures of my tank because it's in some sort of wasteland state, with brown dying acros. That's far from true. I have nothing to prove. My tank has no bearing on whether what I say is accurate or not... yet some people seem to think it does. Ask photobarry (on RC) how they have stopped RTN in the past in their research facility? Then see If you agree with the thread posted. Also wasp I wasn't confused, I saw the two zero's. That's still 3ppb, many reefs operate happily at 0.31ppb (10 times lower than that lower limit). This level is far from starving corals of phosphate. Layton

More personal insults. And I'm the one who ruins threads? You can't even discuss something civilly. How does a picture of my tank relate to whether sudden decreases in nutrients cause TN? Layton

You assume that 0.003 is actually a low level of phosphate. It isn't in terms of corals requirements. That's just orthophosphate you're measuring there. It's around when every other biological store is saturated with phosphate. Coral need very little phosphate to survive. It's not orthophosphate that they need. So your assumption that people should have detectable levels of phosphate in their tank is wrong. That means that their tank is saturated with phosphate. What happens when people do water changes? Do a 20% water change and (assuming the new water has undetectable levels) you reduce nutrients by 20% over a period of a few minutes. Why doesn't that cause problems? What do people recommend people with excessive nitrate problems do? Large water changes > 50%. Does that cause TN? How many people complain about TN after doing water changes? What about when you get a new coral from the lfs. Their tanks could be running an order of magnitude higher nutrient levels. Do people have tn problems every time they put a new coral in their tank? Sure changing SOME parameters quickly can cause problems. pH comes to mind. It controls many cellular processes, determines reaction equilibria etc. But reducing nitrates and phosphates suddenly does not cause the same effect. What about coral researchers who report stop RTN in it's tracks simply by removing the coral from a high nutrient tank, into a low nutrient sea water flow through system? Corals have stores of phosphate. You'd have to see them deplete first before you would see TN due to "low" nutrients. That could take weeks or days. The first challenge though would be to get nutrients that low in the first place, near impossible with the equipment used in our tanks. Layton

Personally I think it is a convenient explanation to explain the occasional trouble people have with the system, without directly implicating the product itself. Same goes for some other commercial products as well. They all have one thing in common, they are adding something to the tank. Surely the logical thing to expect is that it is actually the product causing the problem? Especially when there is no evidence that sudden drops in the nutrients they talk about cause similar problems under other circumstances. Layton

More personal jabs. I was just asking questions. If you can't answer them fine, but does it always have to come back to false assumptions and personal attacks? It's always interesting to here how my tank is doing from someone who is at the other end of the country. :roll: Layton

It's not arguing it's a discussion. I don't buy the whole sudden drop in nutrients causes TN thing. Too many observations which contradict it. Layton

So what sort of changes (numbers) over what period of time are you calling "catastrophically big changes" ? Layton

Some yellow wrasses do, but I think it's a bit hit an miss... like copperbands.

RTN -> rapid tissue necrosis, starts from the tips usually. STN -> slow tissue necrosis, usually seen as slow recession of the tissue from the base of the coral. really only relates to acros and a few sps. Layton

Someone should tell the reefs this info... if it were true, surely they would be long gone with tide changes and weather patterns etc. The common theme is that you are ADDING a substance to the tank then you observe TN. Surely in the absence of any real data, it would be logical to suspect the substance you are adding as the cause? People can also notice these effects well before any nutrient drops even occur. The theory just isn't consistent with other observations. Layton

Depends what type they are, but many of them are unwelcome. White ones are often coral eaters, and can easily kill large colonies quickly. Layton

:roll: So you set out with the intent and desire to "crash" this thread? How gentlemanly of you. :roll: I don't care whether you participate in this thread or not. But if you start assuming I mean something when I clearly don't, i'm gonna call you on it. It's not me getting "upset and abusive", it's me clarifying things. Like I said, you have trouble understanding what I mean sometimes. I don't see how posting information is equated to "crashing" threads. I don't believe I "crashed" any discussion on zeovit, just provided some observations and possible explanations. Layton

Still can't comprehend what you read. Your reading into things just to be argumentative. It gets tiresome sometimes. Layton