Purpose of water changes

[fuz940510]

Hi everyone

Long gap in posting, but life has been a bit hectic. Tank that i was going to use exploded during outside leak test, moved house, started studying etc...

Anywho, my question is: Why do water changes?

The generic, easily available answer is to maintain perfect water quality, but finding good examples of what we're trying to remove/dilute isn't as specific.

Basic ideas that are mentioned are:
1. Removal of nitrogenous compounds (ammonia, nitrite, nitrate)
2. Removing decaying organic matter (left over food, fish poop etc) which can result in phosphate spikes
3. Restore missing trace elements and minerals that get used up

Now, the Triton method for Saltwater got me thinking. To provide solutions for the points above, they would be:
1. Duckweed/floating plants/hang on back "refugium"/riparium for nutrient export
2. Same as point 1, but with a substrate vac for particulate matter
3. Adding an appropriate (confirmed with testing) amount of a gH/kH booster to tank when topping up

Is there anything i'm missing? I know there are the discussions around GIH, but let's leave that out for now.

Good to be back, happy to be learning!
Cheers,
Kean

[Shan_Evolved]

Welcome back to the forums!

I'm new here but my mindset is simple - I feed messy beefheart multiple times a day and it makes my water nasty dirty. I can smell it. Meat spoils and as it breaks apart into cloudy nastiness and I know it gets mixed in with the water so I feel compelled to change it.

I also feel slime buildup on walls and tubes and wood, so when I wipe everything down, it makes the water dirtier as well.

Not to mention sponges pick up bits of food and poop all day, so I gotta give them a rinse as well.

Combined all in all the water gets dirty - fast.

But the number one reason I do my water change is because I love my fishies and want to give them the best.

[jeep]

Welcome back!!! Here's a good link for reading on this subject...

http://forum.simplydiscus.com/showthread.php?120956-What-Are-Bioload-and-Biomass-and-Why-They-Are-Important

[Willie]

It's not about nitrates, phosphates, etc., but more about the bioload. If the inside of your tank is slimy, then the water quality is far from desirable. The article does a really good job explaining the details. Practically speaking, success requires making large, frequent water changes and wiping down the inside surfaces.

The younger the discus, the more important this is. You'll find a thread about a grow out competition elsewhere on the site where the ones raised under optimal conditions show better growth within 2 - 3 weeks. When they're 2" fish, water, frequent water changes is critical. It becomes far less important with adult discus.

Willie

[fuz940510]

Welcome back to the forums!

I'm new here but my mindset is simple - I feed messy beefheart multiple times a day and it makes my water nasty dirty. I can smell it. Meat spoils and as it breaks apart into cloudy nastiness and I know it gets mixed in with the water so I feel compelled to change it.

I also feel slime buildup on walls and tubes and wood, so when I wipe everything down, it makes the water dirtier as well.

Not to mention sponges pick up bits of food and poop all day, so I gotta give them a rinse as well.

Combined all in all the water gets dirty - fast.

But the number one reason I do my water change is because I love my fishies and want to give them the best.
Thanks! Wouldn't that slime buildup be beneficial though, all the extra bacteria?

[fuz940510]

Welcome back!!! Here's a good link for reading on this subject...

http://forum.simplydiscus.com/showthread.php?120956-What-Are-Bioload-and-Biomass-and-Why-They-Are-Important
Thank you! If i'm reading that right, the idea is to make sure that the aquarium has nothing but fish and water - no mulm, no detritus, no nothing. If that is the case, then wouldn't maintaining filters then be seen as being more important?

[fuz940510]

It's not about nitrates, phosphates, etc., but more about the bioload. If the inside of your tank is slimy, then the water quality is far from desirable. The article does a really good job explaining the details. Practically speaking, success requires making large, frequent water changes and wiping down the inside surfaces.

The younger the discus, the more important this is. You'll find a thread about a grow out competition elsewhere on the site where the ones raised under optimal conditions show better growth within 2 - 3 weeks. When they're 2" fish, water, frequent water changes is critical. It becomes far less important with adult discus.

Willie
So the slime containing the benficial and non-beneficial bacteria is best avoided. So the task then wouldn't necessarily be the water change, rather the removal of the slime from the system. Water changes are just the most convenient way to remove this lifted slime

[Willie]

Thank you! If i'm reading that right, the idea is to make sure that the aquarium has nothing but fish and water - no mulm, no detritus, no nothing. If that is the case, then wouldn't maintaining filters then be seen as being more important?

1. Generally, there's very little to filter with regular water changes and wipe downs. I just use sponges for biological filtration.
2. Filters don't remove stuff. It just puts it in a box no longer visible to you. Chemically speaking, it's still there.

Willie

[bluelagoon]

Plus the sludge (slime) hinders the bacteria from getting O2. The bacteria is similar tooth plague attached to surfaces. Filters need regular cleaning, they sludge up too. In time clean water is flowing through this dirty sludge and not cleaning the water properly.

[fuz940510]

That makes sense, thanks all

On to more planning and reading!

[bluelagoon]

It's basically an incubator for anaerobic diseases.

[fuz940510]

I had another thought about this - would a UV steriliser help with controlling the biomass, provided you get it off the surfaces and into the water column?

[bluelagoon]

UV only works on killing pathogens. Does nothing for water quality. There are not many short cuts where discus are concerned, some one would have figured it out by now. There are systems but not for individual homes.

[fuz940510]

To make a quick summary of it, having good water quality is not only down to the amounts of nitrogenous compounds in the water column. Water quality is also affected by the toxins released by biomass that accumulates due to uneaten fish food, fish poop etc.

Rather than just applying the generic name of "toxins", is there any literature documenting what these toxins are?

I find the easiest way for me to understand something is to try and pick holes in the theory behind it. I struggle to do any task if the rationale is "because someone said so" :D

[LizStreithorst]

You can always try your first Discus without doing WC. Experience is the best teacher. But what with all the people who do it this way and fail, we're trying to save you time, money and heartache of going through it yourself.

[bluelagoon]

To make a quick summary of it, having good water quality is not only down to the amounts of nitrogenous compounds in the water column. Water quality is also affected by the toxins released by biomass that accumulates due to uneaten fish food, fish poop etc.

Rather than just applying the generic name of "toxins", is there any literature documenting what these toxins are?

I find the easiest way for me to understand something is to try and pick holes in the theory behind it. I struggle to do any task if the rationale is "because someone said so" :D

When you keep adding elements from the periodic table (in food, conditioners, ect. and there are lots of them) and not talking them back out, they just accumulate and make the water poison(toxic). Simple.

[Second Hand Pat]

Hi Kean, I am not sure you will find a theory on this however please feel free to look about the forum and online. Most people here on the forum recommend large water changes simply because the fish teach us this is what they require to thrive in the little glass box we keep them in. So practice and experience thru the fish are the best teachers. So we are not the ones who say "because we said so" but instead it is "because the fish said so". :D

You also might consider reading thru the threads on the last growout contest we had. Lots of good lessons in those threads. Look under the subforum "Discus Grow Out Challenger Contest 2018"

Pat

[coralbandit]

My belief is there are for more things in the water then we could test for even if we knew about them and believed in them ..
Growth Inhibiting Hormones/Growth Inhibiting Factors [GIH/GIF] is IMO another reason to change water as often as possible while growing fish [not just discus ].
https://sci-hub.tw/https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1095-8649.1977.tb04130.x
I am a big water changer ..
One of my buddies says it best IMO .He says ; " Change as much water as possible as often as possible "..
That sounds a lot better then when he says;" you do flush the toilet don't you " ?:eek:

[captainandy]

Plus the sludge (slime) hinders the bacteria from getting O2. The bacteria is similar tooth plague attached to surfaces. Filters need regular cleaning, they sludge up too. In time clean water is flowing through this dirty sludge and not cleaning the water properly.

Most denitrification bacteria are anaerobic and don't require O2. Nowhere is there more sludge than in our own treatment facilities.

I keep only large adults and I reduce nitrates by growing algae by a device I used in saltwater reefing. That being said I still do 75% twice a week and I can tell that my guys (and girls) love it.

[LizStreithorst]

Barb did it wrong why back this forum was even a twinkle in someone's eye. She knows how to do it correctly now. She only buys small fish and grows them out herself. They get huge like they're supposed to. Next time I give her a call I'll ask her if she will post to this thread.

[bluelagoon]

Most denitrification bacteria are anaerobic and don't require O2. Nowhere is there more sludge than in our own treatment facilities.

I keep only large adults and I reduce nitrates by growing algae by a device I used in saltwater reefing. That being said I still do 75% twice a week and I can tell that my guys (and girls) love it.

Not sure what algae has to do with sludge. You need both anaerobic and aerobic bacteria for the nitrogen cycle.

[captainandy]

Be happy to explain to you. An algae scrubber is a device that you place in the tank or sump that grows algae in a secluded box. The algae, takes up nitrates and phosphates and the device is cleaned out once every couple of weeks. Believe it or not, low nitrates and phosphates are much more critical factors in growing hard corals than in discus husbandry so often used with saltwater tanks

The reference to sludge was to illustrate the fact that water companies cleanse water thru giant anaerobic/sludge filters and containers to remove most unwanted chemicals and pollutants.

[bluelagoon]

Be happy to explain to you. An algae scrubber is a device that you place in the tank or sump that grows algae in a secluded box. The algae, takes up nitrates and phosphates and the device is cleaned out once every couple of weeks. Believe it or not, low nitrates and phosphates are much more critical factors in growing hard corals than in discus husbandry so often used with saltwater tanks

The reference to sludge was to illustrate the fact that water companies cleanse water thru giant anaerobic/sludge filters and containers to remove most unwanted chemicals and pollutants.

I know all that, you didn't need to explain.

[captainandy]

I am so sorry that I offended you. My comments are directed to the readership.
I do not think that algae scrubbers are widely used.

Also, there was concern about sludge and sludge is where anaerobic bacteria live

[14Discus]

Captainandy,

You are prob correct that algae scrubbers may not be widely used. I will add, though, that this guy uses them in all my tanks and wouldn’t go wo after seeing how well they work to eat up NO3/nutrients. Every time I remove algae, I’m removing growth mass that used my tank water’s garbage nutrients to do so. When using algae scrubbers along with a refugium, resin bags, and nitrate reactors, the NO3 levels stay rather low between WCs. Just my thoughts.

[bluelagoon]

There's a difference in algae scrubbers with light and sludge in the filters or substrate. It impedes O2 for aerobic bacteria. If these aerobic bacterium go without O2, too long and then cycle is interrupted, stalled or not preforming as well as there should. But still they are places in the tank and filters for anaerobic bacteria can grow. Plus algae scrubbers are not in the main tank, they are more like a refugium. I had one on my SW tank when I had one years ago.I don't get offended at any of the comments on here.

[peewee1]

We change the water often for the same reason we change the babies diapers. Bio-load. After a while they begin to stink if not changed. With regard to Discus, they are by nature river fish. Designed to thrive in a river. Be it muddy and silt ridden or somewhat clear the river constantly changes the fishes water. They got used to it for however many years they have inhabited the Amazon.

[fuz940510]

Hi all

Apologies for the delay in replying to this thread.

I think my intent behind this thread has been misinterpreted - I am not aiming to find a way around the water changes. There is plenty of evidence (anecdotal or otherwise) that points out that the best practice of surface scraping followed by big water changes, alongside lots of good food, is the easiest way to grow discus big and healthy. My aim/point of curiousity was to find out exactly what effects the practice was having on water chemistry and the aquarium as a system. By listing examples of alternative practices, i was attempting to highlight my lack of knowledge/understanding of the root problem.

The knowledge shared by Mervin (bluelagoon) about toxins, and Brian (jeep) about bioload/biomass has pretty much satisfied my need for knowledge. The information provided is not easily found, so i'm glad i dredged it up :)

Cheers,
Kean

[fuz940510]

And, it seems someone here had similar thoughts, and did an experiment: http://forum.simplydiscus.com/showthread.php?125526-Test-3-%96-Growing-out-discus-fry-with-limited-water-changes-and-plants-algae-scrubber

They just went a bit crazy with the lack of water changes. Even on my current baby tank of green neon tetras and cories i still do a 50% water change every week.

The experiment provided good proof that it's not only about the nitrates though.

[captainandy]

What kind of algae scrubber did you use?

[Ocellaris]

Discus aware a fish that requires some level of work. But if you're feeding normal like bloodworms and some other Foods mixed in and you're not overfeeding. Probably a total gravel vac 70% water change and tooth brushing all of The Hardscape and clean the glass once a week should be enough. I do that in my tank it stays absolutely clear naturally ammonia and nitrates are 0 and nitrates are 10 to 15 PPM I need those at 10 to 15 because I have some live plants it is not a heavily planted tank but has some plants in it. 50 percent water changes every other day the data I'm gathering through water testing is not supporting that as necessary. If you're feeding something messy or you're overfeeding to try and get them to grow out faster, then yeah you might have to do large and frequent water changes. If however you are just enjoying the tank you should not need to do that and I would question someone that says that even though I'm sure they are way more experience and better at discus keeping then I am show me your test results and data that support that level of water changes. I wouldn't call my tank light stock either. And The discus are healthy and happy in fact they just attempted the first spawn sorry if there are typos I'm voice typing this.127414

[Willie]

Here's a shot of my 75 gallon tank yesterday morning. This tank gets 100% water change daily. I also wipe at least the bottom pane every time (yes, I'm obsessive). The fish get 2 feedings a day of beefheart. The rest of the fish, including some rams and corydoras, get Tetra-Bits and the like. One nice thing about barebottom tanks is that the amount of food you feed can be calibrated exactly. Everything was eaten and I know they can't eat more than this.

See how much fish poop is sitting on the bottom of the tank? All this is just one day's accumulation. With gravel and sand, you wouldn't see this stuff. A planted tank with substrate can't really ever get cleaned. Even if I were to vacuum the substrate every day, there would be no way to get rid of all of it.

See those stacked sponge filters in the background? They get squeezed once a week. When I squeeze do that, the water in the bucket turns black. Most aquarists think the tank is clean because the water is clear. In fact, the dirt is just hidden.

[Ocellaris]

Beautiful fish.... but I would suggest that 100%daily is not necessary according to my testing. Does youre testing indicate the need for 100% daily? Maybe with double beef heart it really elevates nitrate levels? Those fish are stunning.

[coralbandit]

Nitrates are not the only reason one should change water .
I am firm believer that we can't test for the most important things ..
I have not tested a tank in over a year myself .
The time it takes to run test you could be half way done changing water ..Which one do you think the fish appreciate more ?

[captainandy]

Many Discus are from an area of the northwest Rio Negra area where it rains so much their habitat probably gets a complete water change every day

[Willie]

The difference between a 50% and a 100% water change to me is ~3 minutes at the computer surfing. :p But to the fish, I think the impact is huge. Everybody here is 6.5"+.

Willie

[Ocellaris]

Yes I agree that water changes do not take very long people make them out to be very challenging. I think that a water change and a full toothbrushing of my Hardscape full vacuum and clean the glass takes less than 20 minutes. So you're saying that for bulk size the hundred percent water change is vital. Okay I can understand that I appreciate the info I met up my water changes to see if the my fish size increases as well. I am not going to go to the beefheart route though. Yeah I could tell those fish were gigantic

[Ocellaris]

Most discus come from breeders unless you have wild caught. So their environment is our tap water assuming the people are doing 50 to 100% water changes daily then yeah that could apply but we're not talking about mimicking the Amazon.

[Ocellaris]

So you don't know you're parameters, and you change because you "think" the fish will appreciate it.... well if the water is testing well or known to be in great condition based on consistent regimen and previous testing, then a water change is a waste of time.... glad we can all see that.

[bluelagoon]

Once you know your water source and get in to a regular routine for that particular tank. I see no reason why you'd need to test your water on a regular basis. Willie will get bigger discus using his method. I've been here long enough to know that about discus. It is very difficult to get 6.5-7.5" discus in a planted tank. I have yet to see them. Lets see the pics and the measure on a ruler to those with big discus raised in a planted tank from a 2" to a 6.5 to 7" discus. I will believe it when I see it.