What Exactly is Old Tank Syndrome ?

Reef Frog

New member
I've heard the term used casually from time to time on RC. But I really don't know what it means. I've never seen a comprehensive explanation of the phenomena.

So besides a bad thing that happens to old tanks, what is it? What are the physical causes? I guess it's biological or chemical, but what are the details? Do animals die off or just lose health and vigor? Is it about bad maintenence or practices?

When does it happen? What can you do about it? Are there early warning signs? How can it be prevented in the first place? Or is it inevitable to some degree?

Well, that's a lot of questions. TIA for any info you can provide.
 
I read that an extremely old tank can have a dominant strand of bacteria inside which eliminates other bacterias. This could lead to easier crashes. To counter this, some folks switch live rocks with others.

I vaguely remember the above while doing research for other things. Plz dont quote me on it. Lol
 
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'Old Tank Syndrome' has been difficult to quantify, but IMO it has much to do with the aquarist 'letting things ride/slide' (Joe Y. coined the term 'LARS', aka 'Lazy A** Reefer Syndrome'). After years of a tank successfully 'doing it's thing' the aquarist tends to get complacent (human nature). Maybe water changes are put off, cleaning is delayed, alkalinity isn't checked as much (if at all), salinity isn't monitored well, etc. Eventually, a 'perfect storm' of maladies hits and 'poof', the system breaks down. It certainly is not inevitable or we'd see every tank experience this (we don't). Smaller tanks tend to be prone to this in less time due to the typically much higher biomass/waste produced to water volume ratio.

The 'dominant bacteria' idea is interesting, but I'm not convinced it's a 'cause'. Rather, neglecting a tank's maintenance can skew conditions to perhaps favor certain types of bacteria over others resulting in unwanted consequences.

Switching LR and LS every 5 years or so was promoted by Dr. Shimek a while back since he believed that they accumulated 'toxic metals'. IMO, it is an unnecessary and a wasteful practice. There are many reefers using decades old material without ill effects, myself included.

There is no 'cook book' to avoiding OTS, but if you examine those tanks that have survived a good long while you'll likely find a reefer who has a good working knowledge of reef tank biology, is consistent with effective maintenance practices, regularly observes the organisms, promotes stability, etc.
 
'Old Tank Syndrome' has been difficult to quantify, but IMO it has much to do with the aquarist 'letting things ride/slide' (Joe Y. coined the term 'LARS', aka 'Lazy A** Reefer Syndrome'). After years of a tank successfully 'doing it's thing' the aquarist tends to get complacent (human nature). Maybe water changes are put off, cleaning is delayed, alkalinity isn't checked as much (if at all), salinity isn't monitored well, etc. Eventually, a 'perfect storm' of maladies hits and 'poof', the system breaks down. It certainly is not inevitable or we'd see every tank experience this (we don't). Smaller tanks tend to be prone to this in less time due to the typically much higher biomass/waste produced to water volume ratio.

I think that's exactly right. I also think there is an inevitable loss of bio-diversity in any closed system that can cause a slow decline as well.
 
IMO it doesn't apply to bare bottom tanks. It is simply an inevitable accumulation of dirt and detritus that builds up over time in a sand bed slowly polluting the system until it reaches the breaking point and causes the system to start declining via excess nutrients, algae blooms, etc.
 
Julian Sprung give a pretty good discussion of old tank syndrome here:

http://www.advancedaquarist.com/2006/10/aafeature

Having multiple systems over 1 and 2 decades old I'd say frequent small water changes are essential to avoid it (not skimmers). As we begin to unravel the carbon cycle and what Dissolved Organic Carbon is doing in our systems and how it's tied to the nitrogen cycle I would hope it becomes much less of an issue. A good introductory book to the role of DOC on reefs is Forest Rohwer's "Coral Reefs in the Microbial Seas". Paper back is about $20 and the kindle version around $10.
 
I have had no luck tracking down information on the topic let alone a standard definition of the term. No surveys, no data, just anecdotal information. When I hear conjectures about causes for such a poorly defined event, I quit listening.

What is probably a fact is that the adherence to an aquarium maintenance schedule declines with age.

Another aspect of the hobby that contributes to aquarium decline is that we do not seem to have reliable, inexpensive diagnostics for the performance of equipment, such as output of lights, pump pressure, skimmer performance, and flow. Without regular performance check ups, equipment decline can go unnoticed for quite some time. Regularly replacing components can be a tough choice when they seem to be working.

Aquarium inhabitants increase in size over time, decreasing the ratio of bioload to biofilter capability. Decreasing flow over the biofilter plays a role in its performance decline. There is no need to propose the decline of biodiversity or accumulation of detritus as "the" cause of aquarium problems, though both can occur.

And maybe contributing to aquarium neglect is the myth often subscribed to: our aquariums are miniature reef ecosystems. If we only follow the advice of experts, and buy the right additive and equipment, our systems will thrive. Aquariums are dynamic, constantly changing habitats that never reach a steady state. They are more like a car on a winding road that needs constant attention to stay on the road while we as the driver are looking in the rearview mirror and reading a book on the theory of driving.

Old tank syndrome is a catchall phrase of little merit.
 
When I transferred all my fish/corals/liverock from my 200 that had been running for 11 years to my 300DD the nitrates stayed a constant 2 to 5ppm in the 200. I never had to worry about algae issues, the tank was in cruise mode. For the next two years in my 300 I had to deal with 20ppm Nitrates and algae issues. Today after 5 years my nitrates are around 5ppm in my 300, I would rather have old tank syndrome than new tank syndrome any day. I believe like others here it is mainly caused by lack of maintenance.
 
There is no need to propose the decline of biodiversity or accumulation of detritus as "the" cause of aquarium problems, though both can occur.

I agree with most of what you've written (the car analogy was excellent), but the buildup of detritus (especially in the sand bed/live rock) is of concern. Not just because of the continuous breakdown of this material degrading the water quality, but mostly that it disrupts the advective flow of water/nutrients/carbon to the bacteria we rely on to complete the nitrogen cycle. High nitrate levels are often associated with this OTS.
 
Julian Sprung give a pretty good discussion of old tank syndrome here:

http://www.advancedaquarist.com/2006/10/aafeature

Having multiple systems over 1 and 2 decades old I'd say frequent small water changes are essential to avoid it (not skimmers). As we begin to unravel the carbon cycle and what Dissolved Organic Carbon is doing in our systems and how it's tied to the nitrogen cycle I would hope it becomes much less of an issue. A good introductory book to the role of DOC on reefs is Forest Rohwer's "Coral Reefs in the Microbial Seas". Paper back is about $20 and the kindle version around $10.

What a great article. My sps tank is almost 4 years old and I recently experienced some weird things. I added several acan frags to the tank. I did already have acans in the tank for 3 years thriving. But all the added acans and the old ones died. Just started STN. My sps colonies are 12-18 inches long grown from frags. And some of them started STN as well. I had to cut out several large colonies before they died. Very weird. It was a perfectly balanced system with huge growth for years and then corals just started receding. I changed 100% of the water and am not out of the woods yet. My tank crashed with no real visible reason on test kits. I learned how delicate saltwater reef aquariums really are this year and how important long term planning of coral placement and specimen induction can play a part at some point in the tanks life. I have decided to do 100% water changes 1 per year now to remove all the old water from the system. I had never done this before this year and It was nice to do.
 
What a great article. My sps tank is almost 4 years old and I recently experienced some weird things. I added several acan frags to the tank.

That sounds familiar. I added a single acan frag to my 7 year old mixed reef tank and within 1-1/2 months lost three acan colonies that were 3+ years old. Luckily, only the Acans were affected (sorry to hear about your SPS).

I believe the new introduction carried a pathogen (virus? bacteria?) that started a chain reaction...
 
Hi, my name is CuzzA and I'm currently suffering from LARS. Well, not that lazy. I still do weekly water changes, but haven't tested my water in a long time. I haven't had to clean my glass in a month, no algae. I guess my tank is doing really well and setting me up for failure.... Hmm, I should go test my water now.
 
Y'know all those trace elements that go on for about a 6" column on your reef salt label. Not all those get used up in exact proportions. SOme get used faster. Things get out of balance. That's my theory. Along with brown powdery gunk/fluff accumulating in nooks and crannies, and places the current never goes.

My cure for slow slide or LARS is an aggressive program of frequent water changes, as in a big 30% water change, followed in several days by a 20%-er, then 4% daily for a long number of days until you've got a lot of replacement. And cleaning up the gunk where you can, with a filter sock in place to catch the crud on the first go-round...but only in very small patches at one time, so as not to crash the tank. IMHO, you probably don't need a total re-start, just a program of water exchange ---easy to dip cups of water out of the sump and toss in a bucket, to throw out, and replace it with an equal amount of salt water.

And of course check expiration dates on all tests, supplements, and lights.
 
It seems totally plausible that certain minor & trace elements on those long lists can deplete and perhaps have an influence on LARS/OTS. But wouldn't the opposite be possible too?

Couldn't it be possible that some elements are building up during all those water changes over the years? Until they reached levels that could set off a rapid decline? Metals Coke to mind.

I wonder if this new fangled Triton method & some of the new testing products about to make their debut could shed some light on things?
 
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