Sorry to be splitting hairs a bit Clive but I think the reason for the water change is twofold - it puts a cap on nutrient levels before they get too high, resetting levels and removing the need for test kits as well as reducing levels of ammonia and algae spores. If it was just ammonia then water changes would be obviated by putting purigen in your filter and perhaps dosing with one of those liquid zeolite products once per week.Nope, the real reason we do water changes is to limit ammonia build up.
Never!!!!!ceg4048 said:If you can forgive the flare from the flash ][/URL]
This is a very interesting question. I would think a filter chock full of purigen and zeolite would pull a lot more ammonia out of circulation than a water change. For example, we have a tank with fish and even shrimp living in it meaning ammonia must barely be measureable. Yet somehow a tiny unnoticeable (to our test kits) ammonia spike is enough to trigger an aglae outbreak. How on earth can a 50% water change once per week help reduce the resident ammonia more than our biological filters, substrates and thriving plants are already doing?ceg4048 said:The problem in high tech tanks is that of organic waste which, when built up to sufficient levels starts to produce ammonia at a higher rate than can be pulled out of the water column by Purigen/Zeolite/Carbon - each of which Barr recommends by the way. Although...thinking about it I suppose you could add a super massive filter completely filled with zeolite/purigen. I'm going to have to check that out Ray. Good point! Barr suggests that substrate vendors start using zeolite in their substrate formulas.
Ray said:How many 6' tanks do you have Clive?! For months I've been thinking "this guy really knows his stuff, his plants must grow like crazy" so its nice to finally see that your tanks are super lush!
That's OK we did wonder and to be honest I'm just a PEARL script re-posting the silliest questions I can find screen scraped from other aquatic forums!ceg4048 said:Wouldn't it be great if it turned out that I didn't even have a tank and that I was just repeating stuff I had seen on the Discovery Channel? Or what about if I wasn't even a real person, just a program written by Matt running on his newly built computer to periodically submit obnoxious posts? What a great story line!
Actually a nice "Dutch" look (I'm not qualified to say if you follow all the Dutch rules, mind). Incredibly lush - very nice indeed.Yes, I know, it won't win any contests , especially with those god-awful spray bars:
Fair enough, sounds plausible.I think Ray that due to the amount of light, bacteria colonies cannot respond quickly enough if there are ammonia spikes. The higher the light, the more quickly the algae spores respond to the spike. Ammonia is constantly being produced at some baseline rate. The bacteria colony population is at a level to consume that nominal rate. To consume the spike the colony must increase it's population but it's response to generate a population increase is slower than the algae can sense and respond to the increased ammonia production rate.
You don't need to speculate - see this quote from the Wikipedia entry on the earth's atmosphere which gives an idea of the kind of atmosphere the original algae evolved in: http://en.wikipedia.org/wiki/Earth's_atmosphere#Evolution_on_EarthI can only speculate that 3 billion years ago when algae were developing, perhaps the nitrogen content of the water was found in ammonia so that became the trigger for their reproduction.
This still puzzles me - by the time you change the water the ammonia spike will be long gone. The background ammonia level is handled by the biological filtration and plants (I expect there is a small spike every night as the plants stop uptake and the bacteria need to adjust). So why do the water change? I remain unconvinced that its necessary to get rid of the ammonia except in order to remove mulm and other debris.Now, strands of hair algae do appear. This is a signal that I should change some water, but I know why I should change it. Not because of excessive nutrients but because of excessive ammonia.
Cheers James. Thanks for the compliment. I firmly believe that the presence and availability of unlimited nutrients/CO2 allows plants to develop their ultimate expression of form and function. Don't look now but I actually stole the general scape ideas from that 120cm on your web pageJamesC said:Wow clive I'm speechless. That is truely impressive and for anyone that says Estimative doesn't work, this is the proof it does.
Thanks for sharing
Hi Ray, Well, remember that the spike is a double edged sword. If you could take a reading, a snapshot in time you would see a spike in the ammonia concentration, but this also indicates a spike in ammonia production, which, given time would be attenuated by bacteria and plants certainly. As we discussed earlier though, this is a race - how quickly can the plants/bacteria respond to the change in ammonia production versus the trigger mechanism of algal spores. By the way, the debris you would be removing with the water change is a contributor to the increased ammonia production as it decays if left in the tank. Therefore removing water immediately reduces the ammonia content, removes the source of ammonia production and removes algal spores which attenuates their response.Ray said:This still puzzles me - by the time you change the water the ammonia spike will be long gone. The background ammonia level is handled by the biological filtration and plants (I expect there is a small spike every night as the plants stop uptake and the bacteria need to adjust). So why do the water change? I remain unconvinced that its necessary to get rid of the ammonia except in order to remove mulm and other debris.
Or you could class it as dosing explosive! Ammonium Nitrate is very handy in that area too!George Farmer said:Hey Clive,
Did you know that the N source in Tropica+ liquid is NH4NO3?
Is that classed as dosing NH4?
Yeah, I know. That's how it reads in my book. I'm such a fanatic that I've decided to purge my stock :!: TPN+ and Brighty are now on my UN Sanctions List...I've got 2 gallons of this stuff left. I'll trade for equal volume of TPN classic.George Farmer said:Hey Clive,
Did you know that the N source in Tropica+ liquid is NH4NO3?
Is that classed as dosing NH4?
If this is true then the big filter choc full of zeolite and purigen is the way to go. I also suggest blowing your ammonia right down the tank to the filter inlet, triggering algae spores as it goes, is an error. :idea: This is perhaps heresy, but I suspect the best way to feed your big filter (or perhaps a big sump) is through an undergravel filter that sucks the ammonia straight down into the substrate before it has any chance to trigger algae spores at all !Algae growth in a high tech planted tank fertilized according to EI methods will be identical whether the weekly water change is 20% or 50%.
Yes, the analysis and conclusions of his research are addressed in the fabulous Nitrogen Newsletter Dated June 2005.Ray said:- We have heard that very small, hard to measure ammonia spikes trigger algae spores in a high tech tank (is there a Barr report or somewhere where this is proven?).
Check.8)Ray said:- We have seen that water changes are helpful to reset nutrient levels but not necessary because, as Clive's experiments show, excess doses of nutrients are not a problem to plants or fish, nor do they cause algae.
Check.8)Ray said:- We have seen that water changes remove algae spores and combined with removal of mulm and decaying matter reduce ammonia production in the tank. Since ammonia triggers algae spores this will reduce algae.
Well, no, I guess I'll have to disagree. The ammonia production rate increase results in the spike. Your assumption is that the spike occurs and then is immediately abated by the consumers of ammonia in the tank (plants, bacteria, algae). At these low levels of ammonia and with the presence of NO3 in the tank the plant uptake of ammonia is not as efficient as that of algae. The bacteria colony also requires time to increase their population in response to the spike. Algae respond to the spike but it does not mean that they consume enough to completely attenuate the spike. Because there is a spike in the production, ammonia continues to enter the system at a higher rate than consumption.Ray said:- We have not seen that water changes actually diminish ammonia directly since the tiny spikes that trigger algae can occur any time and a water change is only at one moment.
Well, see the item above. The more water you remove the more ammonia, spores and detritus you remove.Algae growth in a high tech planted tank fertilized according to EI methods will be identical whether the weekly water change is 20% or 50%.
Let us know how you get on mate. I read somewhere that plants have an 'easier' time using it for their N source than KNO3. I'm no biochemistbotanist though...ceg4048 said:As George alluded to, some vendors use ammonia salts as their source of N, which I find completely astonishing. Probably the levels are low enough if dosed properly, but I don't see the point. I might be missing something so I want to study this some more.
I looked at ammonia additions to tanks a while ago. A few notes for you.ceg4048 said:As George alluded to, some vendors use ammonia salts as their source of N, which I find completely astonishing. Probably the levels are low enough if dosed properly, but I don't see the point. I might be missing something so I want to study this some more.