where/what you guys store 'used' aquarium water?

esoxlucius

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Despite what some people may think, mature aquarium water is rife with nitrifying bacteria and beneficial micro-organisms. Common sense dictates it can't possibly be sterile and at very least, is already proven to be fish safe. I only use established aquarium water for water changes on newly hatched fry racks for example.
This is a strange thing to say, can you please elaborate? There are probably thousands of threads on this site addressing the correlation between nitrate and water changes. It's basic bread and butter stuff of the hobby. Change old water out for new, rule no1 in the fish keeping bible.

I'm confident there are no threads on this site that state that you take your old water out, store it, then stick it back in your tank again the week after.

I'm happy to admit that the water from a heavily planted tank with minimal stocking may have some further use, sort of, but you don't state this. You just threw a blanket over ALL used aquarium water, which for most of us is literally only fit for, well, like I said, flushing down the drain, or watering plants.
 
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fishdance

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It's quite late on my side of the world and the topic is too complex to elaborate but in broad strokes the simplistic 2 step nitrification process traditionally touted in aquarium books and forums is quite outdated.

Other completely different nitrification processes have been studied for a while - some aerobic and some anaerobic (oxygen is kept devoid via specialised
biofilm colonies in aerobic conditions - think Moving Bed Bio Reactors/K1).

Look up Comammox for example - https://en.wikipedia.org/wiki/Comammox
Similarly look up Anammox (anaerobic ammonium oxidation) - https://en.wikipedia.org/wiki/Anammox

Additionally a diverse range of other heterotrophic bacterial and micro-organisms are quite capable of nitrification and do contribute directly in complimentary fashion. It is widely expected that other unknown processes are yet to be uncovered. Even the obvious biofilm colonies with their diverse groups and extremely specialised roles are very poorly understood.

Leaving these other known and unknown processes aside for the moment, the nitrosomas and nitrobacter bacterium groups that most aquarists refer to as sessile will also occur in water columnns, entire, as spores and as replicating fragments. They can and do disperse and colonise new environments via micro droplets in the air (aerosol).

Aquaculture with it's huge water turnover is constantly trying to improve water quality and re-use/reduce it's waste water. I subscribe to several international aquaculture associations and a regular reader of relevant research papers. Not that I am an expert by any means. I work at a large research university
 
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fishdance

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In a more aquarium forum related format, one should never water change hatching fish or very young fry with unknown water.
I run a few hundred tanks so I am always trying to conserve water use as well. Growout racks get 50% water daily.
My largest tank is 100,000L volume so a 20% water change on just that one tank is significant.

Yes, most definitely do re-use water from one rack to another if fish species are not similar.
 
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esoxlucius

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F fishdance , I appreciate those links, it is very interesting no doubt about that. But that information is just about extra "discoveries" in the nitrification process. I'm assuming the resulting build up of nitrate hasn't changed, irrelevant of these new findings?

The crux of this thread is whether we can use old aquarium water, not necessarily just for watering our plants, but storing it and then reusing it in actual water changes too!! The nitrate levels in said used water, unless, as I mentioned, the water is from a heavily planted lightly stocked tank, will surely be too high to give any benefits, hence the reason for the water change in the first instance.

What would be extremely interesting is new information telling us that nitrate isn't as bad as originally thought. THEN, the argument for using old aquarium water in water changes would carry a lot more weight to me.
 
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jjohnwm

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F fishdance , you are frequently making suggestions regarding the latest and greatest aquarium-building materials and techniques, or cutting-edge new filtrations methods, which are always interesting but only in an academic sense to the vast majority of aquarists. A shade-tree mechanic with a couple of cars he likes to work on doesn't really have a reasonable way to utilize the methods that are used in a gigantic General Motors car assembly plant. A hobby shooter producing his own ammunition, one round at a time, on a bench in the basement, doesn't care how a huge Remington plant does it because he simply can't operate that way.

You also discuss all sorts of esoteric studies of the minutiae of water chemistry and biofiltration...again, interesting but unimportant to most of us...suggesting that the common knowledge of the aquarium hobby is out of date...but have no problem using aquarists from a century ago as an example of why water should be saved! As Rick Sanchez might say: pick a lane!

I don't believe anybody has suggested that aquarium water is sterile...but rather that the water itself doesn't have enough bacteria in it to worry about losing those few to water changes. Like the vast majority of aquarists, I don't need to worry about saving every single individual bacterium. Sure, an aquaculture facility...or a set-up as large as yours...would benefit from efficient water usage. The extent to which that goal is worthwhile to pursue will vary from person to person, depending not only upon the cost of water in their particular locale but also the amount which they need.

What you are saying regarding so many facets of the hobby is simply meaningless to most aquarists in a practical sense. For some it's even completely false; I'm on a well, so the only cost for the water I use is that incurred in the initial drilling of the well if it isn't already in place (one time expense amortized over at least my lifetime), in equipment (pumps, etc.) to get the water out of the ground and into my house, more equipment to get it back out of my house and back into the ground, and of course the energy expended to do all this and to heat the water. I have to do all that stuff anyways for simple domestic use. The greatest limitation on my aquarium hobby is the cost of electricity to heat the water; in terms of water quality, I would probably be operating at peak efficiency by not using filters and just having a flow-through system.

But that's just me. Obviously, others in the wide wide world have completely different concerns regarding the cost of water. Since most of those people simply are not going to install the kind of NASA-level systems you frequently and casually espouse...they are just going to have to bite the bullet and decide if the cost is worthwhile to them. Will the cost of maintaining X gallons of water be offset by the enjoyment derived from those many gallons in an aquarium?

With all due respect, I believe you need to gear your presentation of information to the audience in question; when a casual hobbyist mentions a water quality problem in his single 100-gallon display tank, telling him that all he needs to do is buy some sheets of laminated tripolyethylnitrocellulose, a $1000 dollar laser welder and some titanium and construct a 10000gallon high-tech filtration device the size of a bus...is interesting but not really helpful to him. The typical aquarist with one tank...or a dozen...will listen to some of the suggestions you have made in the past...and then look around his tiny apartment or house...and just scratch his head and laugh out loud. It sounds like a good idea for a single-panel Far Side cartoon.
 
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spotfin

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Still has healthy bacteria? No...

The good bacteria that you need and want are not floating around in your tank like noodles in soup or ice cubes in a pitcher...

F fishdance ,

I don't believe anybody has suggested that aquarium water is sterile...
I have used tank water for gardens in the past. The rest goes down the drain. As we are on our own well and septic, the waste water will eventually work its way back to the ground water.
The aquarium hobby is always evolving. No doubt you probably started out with and undergravel filter or air driven filter box with floss and carbon. Bet you still don't use them; I dont. A forum like this should welcome new ideas and be aware of advances in technology regarding our hobby. Granted the technology fishdance mentions is beyond the monetary means of the average hobbyists, in time it maybe. With the recent droughts in this country, people will be forced to find more efficient uses of water. It's all fun and games until your well dries up.
 

jjohnwm

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I guess the two quotes you juxtaposed are intended to indicate a contradiction on my part? There is no contradiction; the water is indeed not sterile, but the number of beneficial bacteria floating around in it is inconsequential compared to the population on surfaces, so much so that the water can be changed without concern regarding the loss of a tiny percentage of them by doing so.

Yes, the tank hobby is evolving, like everything else. I actually started well before UG filters became a commonly-used thing, and originally had no filters at all, quickly moving towards the use of inside box filters with fibreglass (!) and charcoal. I'd consider a sponge filter to be the modern descendant of those filters, but still have a couple of plastic box types on hand in case I ever decided I need to use carbon again (instead of good old charcoal). I don't have an UG filter now, but frankly I wouldn't hesitate to use one if I had the correct size of substrate; I prefer sand when using substrate, so the UG becomes a bit more of a problem.

I'm not against the evolution of the hobby, or of anything else. I have great respect for the knowledge earned through research and experience, and displayed by guys like F fishdance and duanes duanes ; both have a great deal of experience and knowledge...and yet have come to considerably different conclusions regarding some extremely basic ideas like nitrate toxicity. There is no single finite end to learning about this stuff; nobody knows it all; and one doesn't need to know it all to get it to work on the small scale at which most of us are working.

That's the crux of it; it's a matter of scale. The problems faced by a massive aquaculture operation or an individual with hundreds of aquaria are solved differently than similar problems faced by a casual hobbyist. Telling that hobbyist how the big boys do it is interesting...and it might indeed be how people like him will be doing it in the future...but he wants answers right now, grounded in things he can do in his house or apartment right now, without re-inventing the wheel.

Yes, it's all fun and games...whether or not your well has dried up...for almost all of us. When you start proposing that a hobbyist needs to go to extreme lengths to solve issues that can be more simply solved in other ways...you are going to see a lot of them just say "Really? Forget it!"
 

Procrypsis

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I regularly use water siphoned from my delicate shrimp tanks during water change to top off the not so delicate fish tanks. The fish tank water is used for watering plants or flushing toilets.
Yes, even in the good ole USA we conserve our resources.
 
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fishdance

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Apologies if I have upset or confused anyone. I was answering several queries concurrently and my replies aren't very coherent at the best of times.

There is nothing wrong with all the aquarium practices used historically including re- use of old water for months/years. Aquarists used this technique for almost two decades and I'm sure they were better more aware fish keepers than I am as a result. Similarly nitrate reactors, oxygen concentrators, ozone, there is nothing wrong with undergravel filtration, I still use these myself in some situations. My neighbour keeps goldfish in a bowl and knows when a water change is needed just by observation. That's an impressive fish keeping skill beyond me!

Many of the newly investigated ideas can easily be adapted for home use if one is willing. I say this from my own personal experience. Continuously circulating a fish tank or rack through a small outdoor pond for example is qiite easy and reduces possibly eliminates tank maintenance hugely. But to say one type of filtration is superior or will fit every situation would be ridiculous.

This forum is based on monster fish keeping and consequently an expectation of hard won experience and knowledge already acquired exists (in my mind and in my posts).

I'll close this post by mentioning my personal observation is that online groups and forums under the guise of support, can be very competitive, trend setting and undermining of confidence. Don't be afraid to find your own swim channel. It really doesn't matter what others do or buy.

Hopefully the OP has found the information he/ she seeks?
 
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