Slime coat and tank glass cleaning

[t2000kw]

I'm looking through a discus book Discus . . .as a hobby by Jim E. Quarles. Some of the information seems dated, and some of it opinionated.

I came across this bit of information. I will paraphrase what he says in the book here (pages 52-53 in the 1994 edition):

You must clean the entire tank, sides, front, back, and bottom, on a daily basis to remove the slime coat that collects. It collects on the glass, filter, and tubing. This slime on the glass is a perfect breeding ground for bacteria. In a fry tank, this can cause high losses. Wipe the inside surfaces of the tank at each feeding as you clear toe food off the bottom. Foam rubber pads will work for this.

Now, what I'd like to know is if the author is being extreme in this, if he is correct in the need for daily removal of this film, or if he is mistaking the beneficial bacterial coating that builds up in a tank for the slime coat from the discus (since it has a "slimy" feel to it), which is my guess after reading the Walstad book. If the latter is the case, you definitely do NOT want to remove this often as it is part of the ecosystem that turns nitrogen compounds into safe ones.

If I have to clean a slime out of the tank that often, I will reconsider what kind of fish will go in my 55 gallon tank that is being cycled right now in the hopes of putting discus in them later in the fall when I can afford to do so.

I can always do angel fish or find another fish that moves slowly and gracefully and is colorful to look at instead of discus, but I really would like to fit discus into my lifestyle somehow.

[Graham]

He's being extreme and not being very knowledgable....you could never get all the bacteria out of the aquarium or the filters...a sterile environment isn't feasible. Think of planted aquariums........

The bio-film that builds up on the glass and every other surface within the tank is composed of bacteria, diatoms and algae. That bacteria will be a matrix of aerobic and anaerobic species from nitrifiers to heterotrophs, some being non-pathogenic and some being pathogenic.........

Maintaining high quality water and keeping organics out of the system will go a long way in lowering pathogenic bacteria colonies........but they will never be gone. Regular water changes and weekly cleaning the glass of algae will be fine.

The mucus on the fish and the feel on the glass have nothing to do with each other

G

[lhforbes12]

Graham,
I think you may be missing the point on this. Discus have very heavy slime coats which they constantly shed (how do you think it's possible for their fry to actually feed from it?) and this does in fact adhere to all surfaces of the aquarium and can cause some serious problems if left unchecked, especially if there are fry in the tank, but also with all discus. Wiping down the aquarium's glass and other surfaces is something all good discus keepers do. The author is neither being alarmist, nor is he mistaken. Discus do have some special needs and this is one of them.

Larry

[Graham]

Larry the cuticle layer or mucus layer of a fish... any fish...is made up of mucus, mucopolysaccharides, immunglobulins and fatty acids, along with antibodies, lysozymes and protiens . All fish are continually producing this mucus...some fish more than others. All fish continually shed this layer or have it swept away as they are swimming.

While discus are more ''slimy'' than other fish, I doubt that the chemical make up of the cuticle is any different than an angel or koi. They just have more of it and thier fry use it as a basic 1st food source. A lot of fish actually pick on other fish to get this slime, because of it's protien levels...plecos are great at sucking on other fish. If there are articles out there discussing discus physiology I'd love to read them.

As the cuticle continually sheds, it breaks down into it's very basic components forming one of the many componants of DOC's. DOC's don't coat surfaces they just affect overall water quality. So I'll stand by my statement that maintaining high water quality and keeping organics, both solid and dissolved low will go a lot farther in lower bacteria CFU's than wiping the tank down everyday would.

G

[Timbo]

i'm with larry on this one. we get slime on the bottom (and sides) of discus tanks that one does not experience with other fish. i dont wipe mine daily however, every 2nd or 3rd w/c i wipe the glass sides and bottom because detritus tends to stick to it, especially on the bottom. thats one of the advantages of bb tanks...this phenomenon is easily observed.

i believe that this wiping (and most cleanliness maintenance chores) are more important for smaller developing discus than for older, more slowing growing discus.

[Timbo]

As the cuticle continually sheds, it breaks down into it's very basic components forming one of the many componants of DOC's. DOC's don't coat surfaces they just affect overall water quality. So I'll stand by my statement that maintaining high water quality and keeping organics, both solid and dissolved low will go a lot farther in lower bacteria CFU's than wiping the tank down everyday would.

Gby wiping down the tank before w/c's graham, you are lowering the doc's. as previously stated, other detritus tends to stick to the slime, raising those levels.

[CatKing]

Yes, wiping the glass of the tank do help improve water quality. I take turn in wiping the front and side, the back and side, then the bottom during every W/C.
Since I have 24" high tank, wiping the bottom is sometimes giving me some trouble.

[Graham]

Tim take a small aquarium and make sure it's really clean and then set it up as you normally would a BB discus tank except don't put any fish in it.....then tell me what the inside of the tank feels like a week later.

The sloughed off cuticle becomes part of the make up of DOC's and bacteria be they good, bad or otherwise feed off of DOC's. Wiping down the sides of the tank would do very little to lower bacteria counts in the water.

In fact it would do very little to lower bacteria that's adhering to the glass...think about your teeth...you brush them every morning and evening but you still need the dentist to scrape them clean once per year....Bacteria and the matrix that it forms is tough stuff and a bit of paper towel isn't going to get rid of it.

Removing organics and DOC's via water changes and mechanical filter cleanings are what lower bacteria counts.

G

[lhforbes12]

Tim take a small aquarium and make sure it's really clean and then set it up as you normally would a BB discus tank except don't put any fish in it.....then tell me what the inside of the tank feels like a week later.

The sloughed off cuticle becomes part of the make up of DOC's and bacteria be they good, bad or otherwise feed off of DOC's. Wiping down the sides of the tank would do very little to lower bacteria counts in the water.

In fact it would do very little to lower bacteria that's adhering to the glass...think about your teeth...you brush them every morning and evening but you still need the dentist to scrape them clean once per year....Bacteria and the matrix that it forms is tough stuff and a bit of paper towel isn't going to get rid of it.

Removing organics and DOC's via water changes and mechanical filter cleanings are what lower bacteria counts.

G

Graham,
Again, I think you are just missing the point here. Gven your scenario, a ten gallon tank without fish will be MUCH cleaner, a ten gallon tank with fish, other than discus, will still be fairly clean, a ten gallon tank with a single discus will be VERY noticably slimey. I believe the other point you are failing to grasp is that discus have a special slime, again they use it to FEED their fry, it is in fact quite atypical. It has nutrients in it that most other fish do not have. It is, in fact, a magnet for all sorts of bacteria. DOC are a problem for all fish, as you suggest, in the case of discus DOC are an especial problem due to their high demand for clean water and the continual sloughing off of their slime coat. Why do you think successful discus keepers do so many water changes? DOC are only a part of the reason. In this regard discus are extremely different from most other fish.
The author is 100% correct IMO. I'm frankly not even sure why you are arguing this point, a quick search on this site will quickly dispel your mistaken idea in this instance.

[Graham]

Graham,
Again, I think you are just missing the point here. Gven your scenario, a ten gallon tank without fish will be MUCH cleaner, a ten gallon tank with fish, other than discus, will still be fairly clean, a ten gallon tank with a single discus will be VERY noticably slimey.

Hmmmmmmmmm…Maybe we're both missing the point…..there's no reason that the cuticle will adhere to glass, once it's sloughed off the fish, it'll break down into it's basic components adding to DOC's. It's not going in little globs of slime and sticking to the glass. All fish continually slough off mucus and at different rates for each species. Now because there's more nutrient due to discus sloughing off more slime into the water column, the algae and bacteria that grow on the glass may form a thicker layer…hence a more slimy feel to the glass. Even an empty tank will develop a slime layer..

The initial premise that wiping the glass off because the fish's cuticle is sticking to it, makes no sense. The most that you probably would wipe off would be some diatoms, algae and a few protozoa. Has anyone ever done a chemical and microscopic study of what the film on the tank is composed of? Has anyone ever had a CFU count done of the bacteria levels in their water? As I said before cleaning organics out and water changes will go a whole lot farther for bacterial counts than ever wiping down the glass


I believe the other point you are failing to grasp is that discus have a special slime, again they use it to FEED their fry, it is in fact quite atypical. It has nutrients in it that most other fish do not have. It is, in fact, a magnet for all sorts of bacteria.

What are these extra nutrients…is there a study and a chemical analysis of their cuticle showing the differences and what makes it special from other fish?

There are always bacteria in our water, some are non pathogenic like the nitrifiers while others like Aeromonas (this one likes feeding on poop membranes) and Columnaris are pathogenic, while some like Pseudomonas just jump on the band wagon when the opportunity arises. The one thing that the bad ones have in common is the fish must have damaged itself or have lowered immune system for it to be able to invade. A healthy fish of any kind can handle high bacteria counts without problem. Just because a discus has a higher degree of mucus doesn't mean it would get attacked any more or less by bacteria. That mucus layer is full on antibodies etc that give it immunity from bacteria as long at it intact. It's only when that fish is damaged or has a parasite problem that bacteria can get through that barrier.


DOC are a problem for all fish, as you suggest, in the case of discus DOC are an especial problem due to their high demand for clean water and the continual sloughing off of their slime coat. Why do you think successful discus keepers do so many water changes? DOC are only a part of the reason. In this regard discus are extremely different from most other fish.

To be honest with you IMO, discus, and koi for that matter, have been so inbred and hybridized that they have crap for immune systems. None of the fancy coloured ones would last 5 minutes dropped back into its natural environment. They need almost prefect water to keep them alive…..

The author is 100% correct IMO. I'm frankly not even sure why you are arguing this point, a quick search on this site will quickly dispel your mistaken idea in this instance.

Here a week or so ago I ask in a thread if there were any published articles on discus physiology…I got no responses….is everything just ''check the posts around here by some breeder that been keeping fish for a few years. Has no one, done any real science as to what makes these guys tick and why they need pure water…which the wilds don't get

G

[t2000kw]

i'm with larry on this one. we get slime on the bottom (and sides) of discus tanks that one does not experience with other fish. i dont wipe mine daily however, every 2nd or 3rd w/c i wipe the glass sides and bottom because detritus tends to stick to it, especially on the bottom. thats one of the advantages of bb tanks...this phenomenon is easily observed.

I didn't intend this to be a highly debated topic. Most of this discussion centers on a bare bottom tank, which is not what I want to have, so . . .

What advantages and disadvantages regarding the cleaning of this slime would a natural planted tank with substrate on the bottom?

Also, regarding the quote above, what would I need to do to wipe the glass? Is this a quick wipe, a thorough one that you nearly have to drain all the water out to do, or what? I'm trying to get an idea of what to expect if I go the discus route.

If it's too complicated, I will switch to another type of fish. I do realize that discus aren't goldfish (which, the way we have our tank set up, require very little maintenance).

[sleonard]

I'm on the fence on this one. I have read about the wiping glass routine here and initially took it as gospel when I was starting out. The fact that I did get some slime in the tank seemed to confirm it but after some time I noticed a few things: 1) that this slime was only on plastic surfaces not on the glass or anywhere else for that matter. 2) It was no different than the slime in my African tanks and, indeed, it was no different than the slime in my water barrel. 3) I missed a few wipings and noticed no difference afterwards.

This is when I started to wonder if this was not another discus myth or maybe just a little exagerated and greatly relaxed my wiping routine. I still could not notice a difference. Then I switched over to a drip system from a drain-and-fill and am changing at least 150% a day (that will go down when I bring some more tanks online). Any slime I used to get has all but disappeared and this lends credence to Grahams assertion that any fish slime, including Discus slime, will dissolve in the water instead of adhering to and collecting on surfaces. Now that I think about it it just make sense that the slime should dissolve into the water.

I am going to remain on the fence for now and start monitoring my tanks for this more closely than I have been. I have found a lot of very good advice here and have gained a lot of respect for the combined wisdom of the many long-term discus keepers and their advice but that doesn't mean that they can't fall prey to myths themselves. I think one of the long held beliefs about carbon leaching back to the tank was properly dispelled as a myth quite recently.

Regardless of who is correct on this matter, a lot of posts by experienced members to the contrary does not make your assertion false even though it should give you pause.

Scott

[Moon]

Graham makes some very interesting points worthy of consideration. I recall reading somewhere that a scientific analysis of the discus body slime had been done. This was done to determine the food value of the slime. A very high level of protein was found.
I clean the front and bottom of the tank during every w.c. The front for the algae and the bottom where the crap accumulates and mixes with the slime to form a coating. The sides and back are not cleaned and remain green. My discus are doing quite well in this environment.

Joe

[Graham]

Joe you don't have or know where I could get a copy of that data

[gdtrfb]

In short, basic tank maintenance for any other fish tank needs to be stepped up a bit for a discus tank. Your water changes need to be much more frequent. I have a live planted tank without discus and I wipe all sides at every water change - it's just good aesthetic tank maintenance. As for the bottom - which you stated will not be bare, you should also vacuum the gravel much more often than you do for any other tank. A discus tank will require more maintenance than any other tank you have owned in the past. It is that basic statement that you need to assess in your decision to keep discus.. The slime accumulation is a minute detail of the extra maintenance required to keep discus succcessfully. However, the discus tank is very rewarding and not as difficult as aquarium lore might convey.

[Moon]

Joe you don't have or know where I could get a copy of that data

Graham, I think it was in one of the discus books I have owned or read. I would guess it was Discus Health by Untergasser. Will check it this weekend and report back on Tuesday (Monday is a holiday in Canada).
Joe

[Graham]

Appreciate it...thanks

G

[Graham]

I just found this one on line...might this be the one you're thinking of?/



Discus mucus secretions analysed

Discus mucus contains special proteins during breeding.

Molecular biologists have analysed the mucus secreted by brooding Discus and found that it differs from the mucus of non-breeding fishes.

Brooding male and female Discus, Symphysodon aequifasciata, like many South American cichlids, produce a milky mucus secretion when they are brooding fry and the young fish "glance" at the flanks to gain additional nourishment.

It's long been assumed that this mucus contained something important to the development of Discus fry, but the exact constituents have not been studied before.

A team of scientists working at the School of Biological Sciences at the Universiti Sains Malaysia in Penang used sophisticated molecular techniques to determine whether the mucus secreted by brooding Discus to feed their fry contained anything different to the mucus of non-breeding fishes.

Their findings are due to be published in the journal Proteomics later this year.

By studying the mucus secreted by the epidermal cells of male and female Discus during and outside breeding, they were able to analyse the mucus using proteomics and produced protein profiles showing the differences in the mucus at different times. "The mucus of brooding Discus contains many additional proteins that aren't seen in non-brooding fish..."The analysis showed that the mucus of parental fish contained 35 proteins that weren't present in the mucus of non-breeding fish, as well as 18 others that were present at both stages.

By using mass spectrometry, a technique for identifying the presence of chemicals in a sample, the team were able to identify some of the constituents and found fructose biphosphate aldolase, nucleoside diphosphate kinase, and heat shock proteins, which are used in energy provision, producing and repairing cells, handling stress and defense during the brooding period.

The team also believes that breeding Discus must be facing oxidative stress while they're producing this mucus, as the analysis also revealed several antioxidant-like chemicals including thioredoxin peroxidase and hemopexin.

Perhaps of most interest to breeders though is the discovery of a C-type lectin in the mucus of brooding fish, which is believed to provide protection against bacterial infection to both the adults and the fry.

For more details on the findings see the paper: Chong K, Joshi S, Jin LT, Shu-Chien AC. (2005) - Proteomics profiling of epidermal mucus secretion of a cichlid (Symphysodon aequifasciata) demonstrating parental care behavior. Proteomics. (In press)

Matt Clarke: Fri January 6, 2006, 10:50 am
Views: Read 1,602 times




Research Article
Proteomics profiling of epidermal mucus secretion of a cichlid (Symphysodon aequifasciata) demonstrating parental care behavior
Kenny Chong 1, Shashikant Joshi 2, Lam Toong Jin 2, Alexander Chong Shu-Chien, Dr. 1 *
1School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia
2Department of Biological Sciences, National University of Singapore, Singapore

email: Alexander Chong Shu-Chien (alex@usm.my)

*Correspondence to Alexander Chong Shu-Chien, School of Biological Sciences, Universiti Sains Malaysia, Minden, 11800, Penang, Malaysia Fax: +604-6565125

Keywords
Discus fish • Mucus • Parental-care • Symphysodon aequifasciata


Abstract
The discus fish (Symphysodon aequifasciata) is a cichlid demonstrating advanced mode of parental care towards fry. Both male and female fish utilized epidermal mucus secreted from specialized epidermal cells to feed developing fry. We utilized proteomics to compare protein profile from parental and nonparental fish. Gel analysis revealed a total of 35 spots that were up-regulated in parental mucus. In tandem, another 18 spots were uniquely expressed in parental mucus. MS analysis of these spots identified proteins such as fructose biphosphate aldolase, nucleoside diphosphate kinase, and heat shock proteins, which are essential to support energy provision, cell repair and proliferation, stress mediation, and defense mechanism in parental fish during parental-care period. Concurrently, the detection of several antioxidant-related proteins such as thioredoxin peroxidase and hemopexin suggests a need to overcome oxidative stress during hypermucosal production in parental-care behavior. A C-type lectin was also found to be uniquely expressed in parental mucus and could have important role in providing antimicrobial defense to both parental fish and fry. In summary, our study shows that discus mucus proteome undergoes changes in protein expression during parental-care period.



--------------------------------------------------------------------------------

[Moon]

This is a very interesting research study. No doubt funded by Malasian commercial discus breeders.
My information was not as detailed as this study.
The antimicrobial qualities of the body secretions raises some interesting thoughts. It would make sense to keep the fry with the parents as long as possible instead of weaning them on bbs within a short period. Also some form of commercial reproduction of the secretion formula would benefit the hobby.
I used to keep and breed Etroplus Maculatus. The Asian Chromide chiclid. This fish also produces body secretions during breeding. This parent fish would rub the secretion on to the tank sides and the fry graze on it for the first few days post hatching.
Thanks for the info.
Joe

[Graham]

It is interesting, it would be nice to have the full report and not just the abstract...but for $25US...not at the moment

All fish have antibodies within their cuticle, but leaving these fry with Mom and Dad would probably be like leaving a baby with it's mother breast milk...more good things are imparted to the baby.



G