lduncan

I was clear from this post that you missed the point completely: You mis-understood from the get go, which is why I have persisted. I've said that for all intents and purposes orthophosphate doesn't exist unless all sinks for it are full. You've taken that literally, and said that it means that it has to be absolutely zero, not a single molecule of it around. I've qualified it say it means zero like ammonia is zero, ie there will always be some in transition from when it's added or produced until it's found and used by bacteria and phyto. This takes a finite amount of time to happen. This level is well below anything testable by you. Again for all intents and purposes it does not exist in this situation. You know they use the exact same test method and reagents as the Salifert test don't you? They are not accurate enough to be any more useful. Well in order to starve corals of phosphate, first you would have to get phosphate to a point where it is severely limiting (that's total phosphate, not just orthophosphate). To do this of course you'd have to be able to test levels which are orders of magnitude lower than what we are capable of. You would then have to hold it there while the corals deplete there internal pools, then you may stunt the growth, and if it's low enough kill them. I don't dispute that. What I do dispute is the arbitrary number which wasp has stuck on there, 0.02 mg/L (or whatever it was) of orthophosphate. It's rediculous, coral don't require anywhere near that amount. Eutrophication limits are determined to be around 0.003 mg/L of TOTAL phosphate, which is a lot lower than 0.02, and corals require even less than this level. Also don't mistake orthophosphate for bio-available phosphate, they are different. Hach do a test kit for total phosphate. You need to be able to boil strong mineral acids, in order to break bound phosphate into orthophosphate. There are two useful pieces of information which can be gather from our phosphate test. 1. Phosphate is high. 2. Phosphate is ridiculously high. wasp, consider this, what are the two possibilities if bacteria or phyto come into contact with orthophosphate? what are the possibilities if they run into polyphosphate? Layton

Low mag may be dragging the calcium down faster than normal. Seen as calcium is a little lower than what most people run it at (not exactly a bad level though), you can add kalk to try and bump it up along with alk.

Well in a static system you'd need around 150 grams, but obviously the demand for alk is not balanced with calcium, so the reactor can not supply it. So you've really just got to keep ramping up the dosing, until it meets demand. I was adding over 100 grams every couple of days at one point in order to keep up. Layton

Alk can easily drop that much in a day. It's very unlikely that the Alk kit is off. Unlike other test kits, they are not particularly sensitive to light or temperature. What's calcium doing? If it is at normal levels then adding kalk isn't really going to help. Keep adding baking soda to keep up with demand. If calcium is low as well then crank the reactor up. Layton

Orthophosphate, reactive phosphate, inorganic phosphate whatever you want to call it, is the only form of phosphorous which hobby test kits measure. It is the molecule PO4-3. It's the form of phosphate which is not part of an organic molecule like polyphosphate. Layton

All I've said is that they aren't any more useful than any other kit available. Even if it was as accurate as it's precision, then the best you could say is that phosphate is below 0.01mg/L . This tells you that you have a large excess of phosphate in your tank. It doesn't tell you how good your phosphate level is. That's the thing you can't garuantee it. So how do you know that the actual level is not 0.05mg/L? Based on the specifications for the device, that could well be the true reading given the display showing 0.00, you have no idea what the true reading is, just that it's below 0.05mg/L. That's the very reason for these error ranges! It's because you can't just pretend that the number on the display is the true number. If you could, then the accuracies would reflect this. It's only page two. Hyperbole don't you think? As usual your own little argument going on in your head. Who said orthophosphate does not exist in a reef tank? I didn't. Layton

At least someone's following this. You can think of orthophosphate (or reactive phosphate) as a strong oxidiser (in reality it's not in terms of chemistry) in a biological way bacteria and phyto use it. Many bacteria have evolved to take up phosphate in excess of what they need to live and reproduce. Of course there is a limit to what they can store, once that limit is reached they are saturated. So then as more orthophosphate enters the system, it can happily hang around without being consumed. Think of it just like ammonia. When you cycle the tank in the beginning ammonia is detectable because the bacteria which are present are in saturation, they are processing it at their limit. Once the tank has cycled, ammonia is undetectable because bacteria are consuming as fast as it's being created. Ammonia is still present in the tank, but for all intents and purposes it does not exist. As soon as you can measure any phosphate with any kit available in the hobby, your tank has many times the amount of phosphate required by any of the inhabitants. Exactly. This is a point which I've tried to make with wasp before. It seems to have fallen on deaf ears. The colorimeter he uses to test phosphate has an accuracy of +/- 0.04 mg/L plus +/- 4% of the reading, plus and EMC deviation of +/- 0.01. So just like every other test kit, it can only tell you how bad your phosphate levels are, it doesn't have the accuracy or even resolution to tell you how good they are. Layton

Commercial breeders often use small clay pots as a spawning surface. I'd go with ocellaris clowns too. Less aggressive than maroons. Layton

It does, you just don't understand it fully. First off it's not a theory of bombers, it's not even a theory, it's accepted as what happens. If it wasn't accepted, orthophosphate wouldn't be used as a indicator of bad things happening. Second sinks are biological, not physical. Just because you have potential to fill rock with bacteria, does not mean that the rock is only saturated when the maximum amount of bacteria which can fit in it is in it. When a sink is said to be full, it means that the biomass at that instant has a demand which is less than the supply. (It's a dynamic thing, obviously as bacteria die and reproduce) When I say "does not exist" it means the same as ammonia does not exist in a cycled tank. Ammonia DOES exist in all tank, it's being produced and takes a finite amount of time to be used by bacteria and algae. So, if you had a sensitive test for ammonia, you may find that it exists in every tank. Like I said it's the nature of random processes. The situation of orthophosphate when sinks are not saturated is much like ammonia. It exist in tiny amounts, it's produced or added, and it takes a finite amount of time for bacteria and phyto to find it and sequester it. Remember skimmers and systems like zeovit, probidio etc all rely on bacteria and phyto grabbing phosphate in excess as quickly as possible. They would not be nearly as useful if they didn't. You're using a test with +/- 0.04 error though, how is that useful? I can't tell whether my tank is saturated with phosphate or not. I don't have the resources to find out (a Hanna phosphate meter is not a useful test for this). I could take a guess though. Layton

People who know what they are talking about: "Only in recent years have we have learned just how low nutrients must be to maintain healthy coral reefs. The limits were found independently by two researchers working on opposite sides of the globe, who were not aware of each other's work. By looking at the relative amounts of corals and algae along nutrient gradients from intense land-based sources, namely agricultural fertilizers in Australia and bird droppings on a mangrove island in Belize, Peter Bell and Brian Lapointe independently determined exactly the same limit for acceptable nutrient concentrations. Biologically available nitrogen (nitrate plus ammonia) needs to be below 1.0 micromole per liter (less than 0.014 parts per million of nitrogen), and biologically available phosphorus (orthophosphate plus dissolved organic phosphorus) needs to be below 0.1 micromole per liter (less than 0.003 parts per million of phosphorus). In addition concentrations of chlorophyll (in the microscopic plants called phytoplankton) needs to be below 0.5 parts per billion. These values are all regarded as extremely low levels, almost undetectable, in coastal waters of temperate and cold zones. For years researchers measured concentrations in this range but thought that values were too low to possibly cause problems to reefs. This was wrong because they used irrelevant standards for acceptable nutrient levels. It is essential that appropriate water quality standards be applied in coral reef ecosystems if they are to be protected against eutrophication." Yet to see anything which suggests it's wrong. If the sinks are full, then you'll have orthophosphate. If they are not full, you won't have orthophosphate, it is used very quickly (you'll have trace amounts which are in transition but considered negligible) Layton

Nope. Not wrong at all. Layton

tenuis (the default catch all species ) Nah, got no idea, can't make out any sort of axial or even radial corallite shapes, which is generally where you start with an ID, along with general coral shape. Anyway, most ID's are pretty random. There are only a handful acro's that you could confidently ID to 99%. If you want it to sell you have to hype it up a bit, how about Bazzas kryptonite green encruster? (Photoshop's not always evil.) Layton

While it's true that orthophosphate will exist in trace amounts at any instance in time (that's the nature of all random processes), a value of 0.024 is around 10 times the limit people consider to be an indication of eutrophication, which in it self is many times the amount of phosphate required by corals to live and be happy. If the sinks were not saturated it would not exist in excessive amounts like this. The equipment and method you use to measure phosphate is meaningless. All it means is that there is phosphate well in excess of what is really required to have corals live and grow. Orthophosphate is not the only source of phosphate for corals. At these levels it does more harm than good. I'm not under the illusion that because I can't detect it it's not there. You shouldn't be under the illusion that the numbers you get from your tests are somehow more useful. The test's we use can hardly test levels at the eutrophication limit, they're just not suitable for telling you how good your phosphate levels are, they can only tell you how bad they are. Coral researchers have trouble measuring orthophosphate levels in surface ocean waters because the readings they get are below the accuracy limits of the equipment they use, and are infact often recorded at the value of the accuracy limit, even though they may in reality be much lower. Layton

I would be wary of any white coloured nudibranch. They are often coral eaters. I would remove it. If it's like any of the other white nudibranchs i've had, they can cause massive damage (I've monti eating ones, and long before that a much larger soft coral eating one). Layton

Well think of it this way. At any one point in time there is a certain amount of bio-mass. That biomass only has a certain demand for phosphate. Because orthophosphate is the most reactive form (that's why it's sometimes called reactive phopshate) it's used by many organisms in the tank as fast as possible, and doesn't hang around unless it has to. What you're saying here is that there is potential for the biomass to increase, creating more demand for phosphate in the future. Which is all good and well, but it does address the fact that at that particular point in time (for whatever reason) the sinks are full, and there is reactive phosphate just sitting around. From Randy Bacteria and phyto consume orthophsophate as fast as possible if it is available. Saturated means that sinks are full at that point in time. It doesn't mean that sometime in the future there may not be more phosphate stored (due to an increase in biomass), which is what you are saying here. Well it doesn't have anything to do with how much phosphate is there, it has to do with how oxygen levels change. Now you are talking about the dynamics of phosphate, rates of use and uptakes, which complicates things further. Animals are reproducing, bacteria and algae are using it, so how can you say that the phosphate added via feeding HAS to become orthophosphate? And then speculate a timeframe for the tank to "crash". Also I see you are misquoting me again I said "saturated" not "totally saturated". Is that to add dramatic effect? Or to skew what I said to what you like to think I said? It's no theory. This is what allows skimmers to be so efficient. It's what allows the zeovit system and many others like it to work. Layton

Why is it impossible?

Remember how sand beds work though. They cycle between absorbing and release. You can't determine the period of this cycle until it happens. 3 years may not be a long time. It's the same test method. May or may not be any more accurate. Also remember it's still testing orthophosphate. When that exists, all other sinks of phosphate are saturated. Something which you don't want happening. Bottom line, it's still a lot of phosphate. Just think how sand beds work. They absorb first. Also another thing you have to consider, is that it's just a photo. It doesn't show any problems the tank may have had etc. It's just what the tank looks like at a single point in time. Layton

I've had a look around, and it looks like all is related to human's in terms of a particular drug. One thing which would strike me first is that the pH in a tank is substantially different to parts of the body. pH can effect these sorts of binding properties, so I don't know even whether it would be effective in a tank or not. Second, I have confirmed that lanthanum chloride is soluble (as I suspected), which means that all it has the potential to do is bind phosphate. It can't remove it from the system. Then there may be potential toxicity problems to corals and fish too. Cost: around $35 USD for 50 grams Layton

My point was that what appear to be subtle details, can have dramatic effects on skimmer efficiency, and that in the process of copying, some of these details may be overlooked, or compromised to make it easier to mass produce. Layton

All I know about Lanthanum is that it's used in glass coatings in lenses and stuff. I'll have a look around see if I can find out more about it. But if all it does is bind orthophosphate, then I don't see much point, you still have to get it out of the tank. Being a chloride, i'm guessing that it's pretty soluble in water. I'd say that the usual iron or aluminium phosphate removers are going to be cheaper and just as effective at binding orthophosphate. Layton

Notice under the Philosophy section" and Interesting. I wouldn't consider 0.024mg/L particularly low, considering the nature of phosphate. However the tank does look nice. But then I've never said you can't have a nice looking tank with a sand bed. Layton

Also it takes precision to copy a product like a skimmer. Chamber diameters height, throat diameter, water entry angle, pump position, venturi design, needle wheel design and material, etc China is about mass production. Any of these critical parameters can be compromised in order to streamline the mass production process. Also patents are useless unless you can afford to defend them. Layton

Personally I like the idea of having two dosing pumps adding calcium chloride and sodium bicarbonate, rather than a calcium reactor.

But in some circumstances you may be able to. Depends on the size of tank, and what you want to keep in it. Layton

Many plastics do. That's one of the reasons why it's hard for phosphate to be limiting in tanks.