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Water changes

Hi all,
I think the important bit is the plants, once you have plenty of actively growing plants realistically everything else is just froth.

I'd be the first to admit I'm a pretty shoddy fish keeper and because of that I like risk management. It isn't a very exciting approach, but you isolate all the single points of failure and then you try and build in extra capacity and negative feed-back loops.

I have access to <"hundreds of thousands of pounds worth of analytical equipment">, and the staff that know how to use them, but there are still some problems with getting accurate values for all the chemical parameters I might be interested in, and one of the chief problems is time. I can use simple techniques (water changes, the duckweed index, conductivity measurement) to negate the need for water testing.

There is a much more complete discussion of this in <"PlanetCatfish: Cycling Question"> and <"PlanetCatfish:Using deep gravel....">.

cheers Darrel
 
I think the important bit is the plants, once you have plenty of actively growing plants realistically everything else is just froth.
I agree with Darrel wholeheartedly; it's certainly been my experience. By the time the tank matures and becomes biologically stable I doubt it really matters what fertz system you choose to use, even if it's limiting you'll still get some growth and the tank will usually remain healthy. So as far as PPS is concerned, I guess that maybe why success comes with mature tanks only.

I have access to <"hundreds of thousands of pounds worth of analytical equipment">, and the staff that know how to use them, but there are still some problems with getting accurate values for all the chemical parameters I might be interested in, and one of the chief problems is time.
Hobby grade test kits might get you somewhere near the ball park, but again I doubt they are reliable enough to support a fertz regime like PPS which relies on accuracy. Water chemistry isn't my strong point but I'm guessing that if water changes are infrequent there is a greater chance the concentrations of ions or compounds that interfere with test kit results may increase and effect accuracy further. Neither of which is perhaps really that crucial in a mature tank; again maybe why PPS success comes with maturity only.
 
I can use simple techniques (water changes, the duckweed index, conductivity measurement) to negate the need for water testing.

I'm all about the simple techniques (Ideally while relaxing in a chair in front of the tank ;) ), and can add the following to the list:

Observe fish and inverts behaviour
Touch the glass to check tank temp
Watch how much plants are swaying to see if filter is clogged
Listen for pump whine to see if prefilter is clogged
Sniff water when feeding (this is my main indicator and I'm quite evangelical about it!)
Observe all plants for deficiencies
Etc

I also monitor the glass algae, water clarity and time since the last filter cleaning.

These are also on my list.

If you, or anyone else, finds a good link detailing the original pps I'd love to read up on it.
 
Darrel, I have some questions:

....but there are still some problems with getting accurate values for all the chemical parameters I might be interested in, and one of the chief problems is time.

Time for what exactly? Time on the equipment? Time to research the issues? And this:

I can use simple techniques (water changes, the duckweed index...

What is the duckweek method?
 
....I doubt it really matters what fertz system you choose to use,...

This is probably very true. In my search for a dosing/water change strategy, I investigate PMDD, PPS, EI and the ADA method (that I could find), it became apparent that they all have much in common. If I had only a few tanks, and they weren't too large, I, too, would be using something like the EI method. I believe that water changes are a good thing and will always help to make things more stable, but they aren't really as important once a tank has grown in. So for me, with 650 usg of aquariums, it saves a lot of time. We also have some of the cleanest tap water in the world here. So that counts toward the decision I made.

So as far as PPS is concerned, I guess that maybe why success comes with mature tanks only.

Very true.


Hobby grade test kits might get you somewhere near the ball park, but again I doubt they are reliable enough to support a fertz regime like PPS which relies on accuracy. Water chemistry isn't my strong point but I'm guessing that if water changes are infrequent there is a greater chance the concentrations of ions or compounds that interfere with test kit results may increase and effect accuracy further. Neither of which is perhaps really that crucial in a mature tank; again maybe why PPS success comes with maturity only.[/QUOTE]
 
Sorry guys, but I'm now having trouble editing my last post. It ends in the middle and left much of my response on the cutting room floor. I don't have an 'edit' option below my own posts.
 
Hobby grade test kits might get you somewhere near the ball park, but again I doubt they are reliable enough to support a fertz regime like PPS which relies on accuracy.

Somewhere in the ball park is good enough. I need to know if there is none, a little, just enough or way too much of the macros to do PPS properly. The toxicity of these ferts are so far removed from the ranges we need to deal with in a planted tank that strict accuracy is not necessary. [Great, that's what I was trying to add.]
 
I'm all about the simple techniques (Ideally while relaxing in a chair in front of the tank ;) ), and can add the following to the list:
Observe fish and inverts behaviour;
Touch the glass to check tank temp;
Watch how much plants are swaying to see if filter is clogged;
Listen for pump whine to see if prefilter is clogged;
Sniff water when feeding (this is my main indicator and I'm quite evangelical about it!);
Observe all plants for deficiencies;
Etc

Absolutely! Thank you for adding that.

If you, or anyone else, finds a good link detailing the original pps I'd love to read up on it.

Yah, and I guess I would like to know too. I'll try to refine my search better to eliminate PPS Pro and PPS classic. But more later. Hockey game on, gotta go. And since my team tanked early, I all over the Jets.
 
I believe that people will go great lengths to find a way not to do water changes, or at least not very regularly. Regular large water changes eliminate the need of any tinkering, yet, people prefer spending their time in testing in the hope of finding the magic formula or a "system". There is no system that works better than large regular water changes, no matter the tank set up...
Ideally, when one has certain claims about their "magic system", I'd really love the see long term recorded results....Time stamped videos and pictures would do, over the life span of their fish with the least life expectancy....Then I may change my mind....Otherwise it is just useless talk. So, how about some fish pics and videos to see how one's "system" works?
 
I believe that people will go great lengths to find a way not to do water changes, or at least not very regularly. Regular large water changes eliminate the need of any tinkering, yet, people prefer spending their time in testing in the hope of finding the magic formula or a "system". There is no system that works better than large regular water changes, no matter the tank set up...
Ideally, when one has certain claims about their "magic system", I'd really love the see long term recorded results....Time stamped videos and pictures would do, over the life span of their fish with the least life expectancy....Then I may change my mind....Otherwise it is just useless talk. So, how about some fish pics and videos to see how one's "system" works?
This is now being achieved in the Saltwater hobby, so I'd say the magic system is not that far away from coming to the Freshwater side of things.
 
Hi all,
Time for what exactly? Time on the equipment?
Pretty much, for conductivity you can just dip the meter in and get an accurate reading, you don't need to calibrate the meter every time you use it, it has automatic temperature compensation and you don't need to construct a standard curve, or perform serial dilution, but for everything else you need to do some preparation.

If the lab. was all set up and ready to go, it would take probably 1/2 a day to do the tests, and you could run plenty of replicate samples if they weren't too dissimilar in composition.

pH
A pH meter needs two point calibration before every use, buffered on pH7 and, either pH10 or pH4 buffers (dependent upon whether you expect the pH to be above or below neutral), you also need to turn it on several minutes before you use it. Because pH meters are modified conductivity meters they don't work very well in low ionic strength solutions, so you may need to add a neutral salt (a salt from a strong acid/strong base reaction) to raise the conductivity without changing the pH. I use KCl (NaCl would also do), but it has to be the pure salt.

Also the pH probes are quite high maintenance bits of kit, and need to be stored in the <"appropriate storage solution"> (usually 4M KCl).

Ion Selective Electrode
Accurate measurement of NO3 and NH3 you can do with an ion selective electrode, you need a hot plate stirrer and to construct a standard curve. To measure ammonia/ammonium (NH3/NH4+) the ammonia ion is liberated as ammonia gas on the addition of an excess of sodium hydroxide (NaOH):

NH4+ + OH– → NH3 + H2O

The outer membrane of the electrode has pores that allow the ammonia to diffuse through it. The change in the pH value of the inner electrolyte solution is then monitored by a combined glass electrode. It works, but it is a bit fiddly.

Ion selective meter and their electrodes are quite expensive and the gel membranes have a limited life span.

Atomic absorption spectroscopy
Metals you can measure directly from the filtered water via AAS (or ICP), you need a calibration curve, and you may need to dilute your sample with DI water if it has a lot of Ca++ ions etc. The method is fairly straight forward, you have a controlled flame (using air/acetylene for the AAS) and the filtered sample is sprayed into the flame (as very fine droplets <10 μm) and the spectrum produced read at the appropriate wave length for the element you are interested in. The light source used is a hollow cathode lamp, you need lamps that cover the elements you are interested in.

Spectrophotometry
Phosphorus (as PO4---) you can measure with spectrophotometry, using the intensity of colour of a phosphomolybdate complex. You need suitable reagents, you get interference from some other compounds, and you need to construct a standard curve etc.

cheers Darrel
 
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Hi all,
This is now being achieved in the Saltwater hobby, so I'd say the magic system is not that far away from coming to the Freshwater side of things.
This is actually easier in sea water, because you have a known composition (a datum) and you can take into account the 33 ppt NaCl etc.
Somewhere in the ball park is good enough.
Yes pretty much, in a planted tank, for some parameters, even an order of magnitude of latitude isn't going to matter that much.

The really critical ones, like dissolved oxygen and ammonia, are much less likely to be an issue in a planted tank.
What is the duckweek method?
It is just a method where you use the heath and growth of a floating plant as an indicator of when to feed your plants.

It came about because we did some work on the remediation of landfill leachate, a liquid with a very high BOD.

Because landfill leachate is highly coloured, full of colloids, greasy and of wildly differing composition dependent upon rain-fall age of the landfill, the type of rubbish land-filled etc., it is really difficult to quantify chemically.

One way of treating it is to use the sort of primary treatment you have in a sewage works followed by secondary and tertiary treatment in "constructed wetlands". Hopefully following treatment the resulting water is of sufficiently high quality to fulfill the requirements of the discharge license.

In the landfill we work on, the water almost always was of poorer quality than was required for discharge. We looked at ways of improving the final quality and using indicator (bioassay) organisms as an alternative to chemical analysis.

We found that you can use trickle filters and phytofiltration to produce water that has a low enough BOD for discharge, and you can confirm the water quality by using Daphnia, Asellus etc. Originally we used <"Lemna minor"> as our floater, hence the "Duckweed Index".

Have a look at <"Which NO3 test......"> and <"New Hi-Tech set up">.

cheers Darrel
 
Darrel, that's terrific. I did research in a lab like that many years ago, during a hiatus from this hobby. Cheers for the post.
 
pH
A pH meter needs two point calibration before every use, buffered on pH7 and, either pH10 or pH4 buffers (dependent upon whether you expect the pH to be above or below neutral), you also need to turn it on several minutes before you use it. Because pH meters are modified conductivity meters they don't work very well in low ionic strength solutions, so you may need to add a neutral salt (a salt from a strong acid/strong base reaction) to raise the conductivity without changing the pH. I use KCl (NaCl would also do), but it has to be the pure salt.

What level of accuracy do you maintain without doing all that? I recently recalibrated ours after about a year (having used it a couple of times a month and just stored it with the lid on) and it was 0.1 out. The readings between tests seem to remain stable, and adjust as expected to changes in the test water.

Not saying that it's as accurate as it would be with that level of maintenance, but more so than the dip/test kits, and seems like enough for aquarium purposes.
 
..... Originally we used <"Lemna minor"> as our floater, hence the "Duckweed Index"....

I use Sylvania to assist me with algae outbreaks when I'm doing a new tank. It provides some shade, soaks up excess nitrogenous waste and is reputed to have algae growing symbiotically in its roots thus creating a bit of a nutrient vacuum for certain types of algae (not sure about that last bit, but I throw everything but-the-kitchen-sink at it so why not, eh?). I wonder if it would provide the same results? It certainly grows differently in some of my tanks, and is especially noticeable between planted tanks and fish only tanks or tanks without CO2.
 
....Otherwise it is just useless talk. So, how about some fish pics and videos to see how one's "system" works?

Ok, fair enough. I've posted photos on photobucket with links below. All of these photos have been taken after December 2012 which is when I started using PPS, and they've been up and public for a long time. In advance - sorry for the ads. Photobucket has become one of the most abnoxious sites I've ever been on. If I did more of this I'd find another. But for what it's worth:

http://s1157.photobucket.com/user/wolfewill17/library/story_3715?sort=6&page=1

and

http://s1157.photobucket.com/user/w...Tank/P4093915_zpslsv6bnjl.jpg.html?sort=3&o=0
 
Some nice growth in the bottom lot of shots.
And crikey, I see what you mean about obnoxious, photobucket has almost become unusable.
Have you tried Flickr, I transferred all my images there just before photobucket started to charge.
https://www.flickr.com/photos/99942601@N07/
 
And here are some pics that were on my web site when it was in operation. All of these tanks were, and still are, PPS dosed. In order from top to bottom:
A 65 g tank with large Bleeding Heart tetras, etc.
Next is my other 65 g, again before it's most recent o'haul. The Lemon tetras are hiding due to the back light.
The third one down is the 330 g tank with in it's first setup. It's on its third setup now. Recent pics haven't been taken yet.
The bottom one was my 90 g before the 330 was installed. I've also overhauled it recently but it's not grown in completely yet.
I have records of every weekly set of tests I've ever done, of every week of dosing for each tank, records of exactly when each tank had a water change and every bit of maintenance each tank has had during routine maintenance days - all back to 2012 and for water changes to 1995 (I'm a pathological record keeper). But these are all hand written and would be very tedious to present and undoubtedly very, very tedious to read through.
N65 (800x482).jpg
O65 (800x600).jpg
PC312653 (800x600).jpg

M90 (800x398).jpg
 
This is now being achieved in the Saltwater hobby, so I'd say the magic system is not that far away from coming to the Freshwater side of things.

What do salt water creatures have to do with fresh water....Even the
This is now being achieved in the Saltwater hobby, so I'd say the magic system is not that far away from coming to the Freshwater side of things.

And how do you think would that be replicated in fresh water set ups....taking into consideration all the fundamental differences between fresh watet and salt water....? Anaerobic denitrification....rising TDS....nitrite toxicity, etc....
 
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