ctgretzky99":1aeypuv4 said:
I didnt know how to quote individual things...lol...so bear with me:
[ quote ] starte the quote and [ /quote ] stops the quote (only with the spaces removed)
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BOB: I know it is hard to understand. So please run the numbers to see for youself. Say 100ppm nitrates should be 0. 10% change and they are 90. Another results in 81. the next 81-8.1 etc etc. they never get to 0.
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Ok, running the numbers lets start with a realistic nitrate of 40, not 100. If I do a 10% change of water, I have reduced it by 10%, or now a level of 36 ppm. This by your math, but it isn't really accurate. Because I am removing 10% of the water, then ADDING 10% back, I have actually reduced the nitrates by 20%. Get that? It is actually a 20% swing. Now depending on the tanks ecosystem, and if I am diligent on my testing, I know my tank takes appx 2 weeks to build up that 20% difference, so I will do a water change once a week until it is stable. Thereby if I keep up with the tank, eventually I can keep my nitrates at a lower value and easily sustain it.
I'll give you and even scarier example. I first set up my 20g as a hospital tank. I left town for 4 days and a sick angel died and was badly decomposed in the tank when I returned. At that time I finally discovered salt macros and added macros. nitrates were 120-160ppm++ (red in the aquarium pharm***** test kit). With no water changes nitrates were 0.0 in three weeks. Your math is incorrect. You remove 10% of the nitrates and replace that water with 0 nitrate water the nitrates are reduced by 10%. With weekly 10% water changes the nitrates would have been 81% of the 120-160ppm+++ or not even noticable with the test equipment used. But with macros and no water changes and replaceing evap water with water containing some nitrates, the nitrates were 0. Again tanks are not static things. There are forces at work to make them better. Those forces are more powerful than water changes IMO
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BOB:If livestock consumed trace elements and the only source of trace elements was the water, then you are correct the trace elements will be lowered. And they will be lowered slower with water changes then without. So again the situation is not corrected with water changes, just that the changes (downward in this case) is slowed. So that something that may have become critical in a month becomes critical in six months to a year. but they will still become critical.
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I dont get this line of logic at all. The ONLY availability of trace elements comes from the water. Period. It doesnt come from the Live rock, plants do NOT contribute ANY trace elements, and there isnt anything else in the tank that can do this. Only by adding trace elements can there be any at all. Show me one study anywhere in the world that shows that the photosynthesis of plants or anything else in the tank adds magnesium, calcium or any other needed trace element and I'll never wite again. Unless you are adding seperate agents yourself, tank depletion is going to happen over time.
you are simply wrong on this. I can't state it any other way. Trace elements are added with the food. calcium carbonate rocks, substrates, aragonite sand, and filter media do buffer calcium, carbonate and magnesium.
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BOB:Trace elements, calcium carbonate, magnesium, and the like come from more sources than the salt water we make up. Trace elements are added through food which comes from the marine animals and plants which needed and accumulated those elements while alive.
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This could be true, I don't know off hand, so I can't say you are incorrect in this point. However, the availability of such trace elemens is limited to a small amount of time, and thereby isn't readily available in the water if needed.
the trace elements are provided to the fish and corals through the food. And remain in the system.
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BOB:Calcium carbonate and magnesium can be added through buffering substraits and filter media. And replacement water can contain those elements also.
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Yes, replacement water...isn't that what we are talking about? Are you saying that through replacement of evaporated water only that this can be accomplished? If so, you never stated that, and it can make sense. If I evaporate 5 gallons a week, it can ALMOSt be considered a water change -with replacement...I'll get to that later
Yes. replacing the evaporative water with tap does add those elements. RO/DI less so. Not the same as a water change. No salt is added.
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BOB:Yes the plant life does bioaccumulate those things. And the bioaccumulation is porportional to the concentration of those elements in the water column.
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Not true. As a horticulturist, I can tell you plants do not readily absorb and dissipate any of the elements needed to sustain a salt water aquarium that I know of. Granted, I know about earth-borne plant life, but I am figuring a photosynthetic lifeform acts the same in or out of water. The small amount of elements is only available through the death and decay of the plant life.
You are correct that there are several similarities between land plants and saltwater plants. The main point is the plants remove those from the water at a rate that is porportional to the concentration of those things. that helps maintain those levels. environmental engineers are even using dried seaweed to remove toxins from industrial waste water. Just as copper and other toxins are removed from our tanks. At very high and lethal concentrations the bioaccumulation is also very high. then harvesting those macros removes them from the system. Again a dynamic consideration. Not the static I have an ion of copper, zink, lead, or cadimum that goes from coral and coral killing everyone. That is until it is removed through a water change. What actually happens in nature and our tanks, is those things are maintained a levels that substain life in our tanks. Just as the rivers with those things are processed by the plant life in ocean lagoons and reefs, allowing the reefs to thrive.
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BOB:Yes it is hard to understand and comprehend. Especially when every person you talk to tells you differently. But once there, the tank simply maintains itself. Without your interferring water changes.
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Now I noticed the pics posted are from a while ago, nothing new. I can say this-any tank that has added water because of evaporation, and has buffers/trace elements added and that relies on a bio system to support it can last-for a while. I understand the reason behind your method, and it is actually interesting and functional to a point, but not in the long term.
Have ran FWs and FOs for up to 6 years continuous, my currrent reef for about 2 now.
You speak of a long drawn out death for a tank with water changes, but I say that is exactly what you are proposing by having a closed system.
just for the record I stated that things will not be corrected with water changes alone. That does no mean a long drawn out death. But it can hide underlying problems. In my 55g I think the low calcium many have been delayed for a year or two. And the results of my solution were readily visable because I was not changing out the water.
I could be wrong, I mean refugiums weren't really accepted at first by the everyday hobbyist, yet today that is what more and more people are using. But they still do water changes.
This method of yours, if you are being honest in the condition of your tank, may even work for you as in a small way it makes sense to a degree. However, i think it is dangerous to post for someone new to the hobby unless you do a few things:
1. give us a complete list of your tank equipment
2. Tell us your exact readings/parameters and their swings
3. tell us your bio load-anything living as fish, invert, coral
4. tell us what plants you use
5. how old the tank is
6. your weekly/bi-weekly routine as far as replacement of water, feeding and what kind of food
anything else to help us understant the complete bio cycle. To say i have some plants and i dont do water changes is not convincing me, and not to have updated pictures on a constant basis to prove your method scares me.
the complete bio cycle will never be fully understood. but here is my tanks
fw:
tank
sand
water
plants
fish
lights.
4 years currently one 8 years with 6 years in one location. about a dozen tank over the years.
no testing of any parameters.
reef
55g
3" silica/quartz HD play sand ($3/50#)
lava based base rock with one quarts geode
salt
tap water untreated from the cold faucet
external sump/refug 15g with 1" play sand and diy filter box with crushed oyster shells.
mag5 pump pumping 4' for external sump/refug
4'x2' egg crate 3" in front of back glass (in tank refug)
2 4' utility fixtures 2x overdriving 4 tubes (~55w each) tubes are 6500k ~2900 lumen t-8s
2 4' utility fistures 6" behind back glass pointing forward to light up the in tank refugium. 4100k 3300 lumen tubes.
lights are on x10 controller.
ammonia, nitrItes, nitrates undetectable
ca 400ppm (~385-425 but usually right on 400)
alk 2 meg/l (drops are calibrated to measure 1.5 then 2 the 2.5 etc)
mag 1100ppm.
ph 8.2-8.4 (purple on the aquarium pharm**** test kit) just before lights off
ph 7.8 (brown on the test kit) measured one time just before lights on.
I am using chaeto, caulerpa profilera and caulerpa racemose (grape), new halimeda and a ref fauchea sp.
I stopped weekly testing 2 months ago because nothing was changing. I did test calcium a week ago because I added several halimeda which consume calcium. Calcium still measured 400ppm.
in both snails and other cleaner crews came in on the plants and macros. So kinda a built in cleaner crew.
