Old tank syndrome?

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So the YouTube thing got me onto a couple videos about this “old tank syndrome” thing.

I’ll preface this post by saying that I have NOT done my homework entirely on this subject... So I’m after long time fish keepers input on this one as part of my reading.

Essentially, what I’ve been able to conclude, is that it is a gradual build up of nitrates and other nasties over time that your fish become accustomed to slowly. Then it becomes almost unbearable to new fish added to the aquarium and there is a toxicity of nitrates and other things that will almost always kill off new fish.

what a time to come across this new possible tank situation, as the weekend just passed was supposed to be my filter, tank deep clean weekend.

but because of the varying levels of my concussion recovery, I opted only for the 25% water change (with the gravel vac).

I’ve also deducted that this condition of water quality is brought on mostly by lack of weekly maintenance and just “topping up water” instead of changing water out.

Im down to checking water once every two weeks, because the parameters don’t change much week to week.

In the spirit of being diligent, I checked tonight, everything checks out okay, except the nitrates have gone from being just over 10ppm to just under 20 ppm in a week.

I feel that’s pretty significant, and because this tank is getting to that mature stage, I don’t want to make any major changes, so the question lies in, do I do some bigger water changes and get nitrates down, or do I wait it out and clean the tank/filter out this weekend?

i have no fish in quarantine to add to this tank, and the fast growing plants I have are going crazy with new growth.

i also keep a sponge over the intake of the canister filter intake, and that gets cleaned in tank water with every weekly water change. It significantly reduces the debris build up in the canister filter media.
 
Also, if any part of that post doesn’t make sense, remember my brain got rattled...

so I’ll happily clarify any confusion.

scratch that, I’ll happily TRY to clarify any confusion
 
I dont think you have to worry about old tank syndrome because your nitrate rose 10 ppm in a week. This build up of nitrates is quite normal.

I would attribute old tank syndrome to a tank that has been neglected in terms of its water changes which has caused the KH to become depleted over time to a dangerously low level. The KH, or carbonate hardness, would normally buffer the pH against wild swings but when it is depleted or non-existent the pH will swing wildly in response to new stimuli, including new water addition. This can often cause fish to become stressed or even die.

With the above said I would go about testing your pH and KH of both your tank water and tap water. If your KH is below 3-4 dKH and/or the pH readings differ then you should consider doing smaller and slower water changes to counteract any pH swings. You should always be doing filter sponge cleaning regardless.
 
but because of the varying levels of my concussion recovery, I opted only for the 25% water change (with the gravel vac).
I missed something. What happened to you?

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Essentially, what I’ve been able to conclude, is that it is a gradual build up of nitrates and other nasties over time that your fish become accustomed to slowly. Then it becomes almost unbearable to new fish added to the aquarium and there is a toxicity of nitrates and other things that will almost always kill off new fish.
That pretty much covers it except as the nitrates go up, the pH usually comes down and you end up with really high nitrates (above 100ppm and sometimes above 200ppm) and a really low pH (5.0 or less).

Old Tank Syndrome happens over a course of months (usually 6 months or more) and is from lack of tank maintenance (water changes, gravel cleans, filter cleaning). People stop doing water changes and just top the tank up with tap water.

Fish waste builds up and create acids that use up the KH in the water and cause the pH to drop. The nitrates go up and the number of disease organisms in the water increases to a point where there are literally billions of microscopic pathogens in every drop of water.

Some of the fish that are in the water while it degrades over time, adapt to it, others die. However, when you add new fish to the tank, they suffer from nitrate poisoning and or acidosis (sudden drop in pH) and they usually die straight after being put in the tank. Some fish might survive a short time but usually die from disease.

Someone comes along and decides the tank needs a clean, so they drain most of the water out and gravel clean the substrate, maybe clean the filter and fill the tank with clean water. The fish then go from horrible old water full of harmful disease organisms, hormones and other chemicals released by the fish, acid water and really high nitrates, into clean water with a higher pH and lower nitrates. Subsequently most of the fish up and die from shock, usually alkalosis (sudden rise in pH).

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How do we fix Old Tank Syndrome?
Small daily water changes and gravel cleans, and cleaning the filter.
Do a 10% water change and gravel clean the substrate every day for a week.
Then do a 20% water change and gravel clean the substrate every day for a week.
Then do a 30% water change and gravel clean the substrate every day for a week.
Then do a 40% water change and gravel clean the substrate every day for a week.
Then do a 50% water change and gravel clean the substrate every day for a week.
Then do a 50-75% water change and gravel clean the substrate once a week or once a fortnight from then on.

This method of doing small water changes allows us to slowly increase the pH and dilute the nitrate and puts less stress on the fish.

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How do we prevent Old tank Syndrome?
Do big regular water changes every week or two, and gravel clean the substrate whenever you do a water change.
Clean the filter at least once a month.

Make sure any new water is free of chlorine/ chloramine before it is added to an aquarium containing fish or other aquatic life.

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As Mark4785 said, an increase in nitrates of 10ppm over a week is nothing to worry about and is pretty normal.

You won't have to worry about Old Tank Syndrome if you miss a water change here and there. If you slack off and don't do any work on the tank for a few months, then you start to worry.
 
I agree with @mark4785 If you believe you have OTS the best way to determine if your tank is healthy is to look at your KH. I use Seachem Alkaline Buffer at half the recommended dose and it has helped bring everything in the tank to a happier state.

I battle inconsistent water quality so can't rely on my water changes to bring all the parameters to a predictable state. I tried to do a water change and had to wait hours for the water to clear before I could attempt it.

This is what it looked like right out of the tap (yuck!)
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There are other ways to raise KH, but this has worked quite well for me. I have heavily planted tanks that deplete nutrients quite fast, so making sure that the quality of the water is good becomes an important part of water changes.

I hope you are feeling better. Concussions are nasty.

Yikes!
 
In the spirit of being diligent, I checked tonight, everything checks out okay, except the nitrates have gone from being just over 10ppm to just under 20 ppm in a week.
The typical test kit checks for ammonia, nitrite, nitrate and PH. That is often not enough to detect the early signs of a problem. Add a GH and KH test you still are not likely to see it coming.

if you test about 22 different parameters you might see it comming.
Im down to checking water once every two weeks, because the parameters don’t change much week to week.
Your water change schedule should not be determined by Ammonia, Nitrite,a dn nitrate levels. And a 25% water change still leaves 75% of all the waiste is left in the aquarium. And it might not be enough to replenish carbonate levels or GH levels.

This video about water changes is in my opinion good visual illustration the issue with water changes. IN my opinion anything less than a 50% water change will not maintain stable water parameters.

Also old tank syndrome means different thing to different people and can be very different between a fish only tank and a tank with fish and plants.

For a fish only tank the main problem is that mainly about the mineral salts and gases in the water. If your water change is not enough the mineral ocncentraion may build up over time until it gets out of balance and your fish suffer. Also organic buildup in substrate could cause a buildup of toxic gases as it decays. For a planted tank if you plants stopping well thecommon cause in my experience is a mineral deficiency. If the mineral nutrients in the water get out of balance plants and fish can suffer.

One old tank syndrome hits it might not be possible to rectify the situation with a lot of water changes. You might have to change the substrate to correct the issue. Some people use dirt or manufactures plant substates. These nutrient rich substrates to get good plant growth. As the substrate ages the amount of nutrients it release will fall until the plants no longer grow. In other cases and old substrate may start to release silicates or something toxic. In either case the only solution is to replace the substrate.
 
Or follow @Colin_T 's advice. He was typing at the same time I was, but I would trust his advice over mine. :)
Your brown tap water looks disgusting :(

I'm not sure how I would have survived back in times gone by when they drank brown river water.
 
Interesting thread and some really good info in here :)

Just wanted to add that its really important to put your tank in a holding mode sometimes if 'life' takes over something like a concussion is serious so you shouldnt put the pressure on yourself to have everything pristine as usual.

Wills
 
Without good water changes, stuff builds up, particularly acid. Nitric acid from nitrates, tannic acid from tannins leaching from bogwood, humic and fluvic acid from biodegradation of organic matter.
All of these acids build up and lower the PH (and KH). Once the PH drops below 6.8, ammonia starts to convert to ammonium. Ammonium is nowhere near as toxic as ammonia.
<<This bit might be incorrect, but I've read it somewhere before... >>
The same BB responsible for nitrifying ammonia cannot process ammonium. There are other organisms that work in low PH waters with ammonium known as archaea.

So at this point, you have an acidic tank with lots of ammonium. As previously said, ammonium is relatively harmless to fish and so you don't notice any problems other than a high reading of nitrates.
If you did a water change now and raise the PH above 6.8, then the ammonium would revert back to the toxic ammonia.

The combination of the ammonia and swing in PH is what kills the fish. Thats my understanding of OTS!
 
A month, two, or more of neglect creates a downward spiral of water quality. Some fish tollerate and survive, other do not. Some are deluded thinking that if nitrates remain fairly low, then water chemistry must be good. The trouble is nitrates keep bad company with other pollutants that are not measured. Some forget that nature refreshes fresh water all the time with rain and snow melt. I generally like to say "there's no such thing as too much fresh water", but old tank syndrome is the exception. As @Colin_T points out, rapidly changing the water chemistry, even for the better, can shock the fish. (I hope you are on the mend from whatever happened).

 
I missed something. What happened to you

I got a concussion when I was rear ended Friday before last. Sparked the whole “learn to drive...” rant I went on.

still fuzzy in the head, but I’m getting help with physio and talking with an occupational therapist several times a week. Unfortunately, I have had a couple before, so I’m in for the long haul on recovery.

anyways, there are a bunch of great replies, so thanks for the info everyone. I don’t think I have old tank syndrome, but I do think I’m going to up the amount on my water changes.

also, I’ve got the gh and kh test kits on my shopping list, just waiting for the funding to be there, but I think I’ll just make it happen sooner than later.

as for the substrate, I was thinking about upgrading the size a bit, and I have a new substrate picked out already, that’s a month or more away at the moment.

anyways, thanks again everyone. Great stuff.
 
I got a concussion when I was rear ended Friday before last. Sparked the whole “learn to drive...” rant I went on.
Gotcha. Lots of rest and no sudden shakes to the brain because it takes a while to recover.

Get a camera and start photographing your fish :)

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I’ve got the gh and kh test kits on my shopping list, just waiting for the funding to be there, but I think I’ll just make it happen sooner than later.
You don't normally need to test the GH and KH regularly unless you get water from different sources. Most tap water has a pretty stable GH and KH and lots of people simply get their local pet shop to test it a couple of times a year. However, if you want to buy the kits and test it regularly, that is also fine.

Check the expiry dates on the test kits and make sure they aren't kept in a warm, humid or brightly lit place because heat, light and humidity cause the reagents to break down quicker.
 

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