Stocking Clarity

[fenny666]

Hi

Although this is only my second post I have used this forum for a while sifting the comments for valuable tips.

One of the topics which comes up alot is stocking levels.
Reading around the web ,alot of advice goes towards cm of fish/litre etc. or surface area.

While these play a part I think other factors which are often overlooked (or not given the importance they deserve) play a much more important role.

For example - take a 60l tank ,internal filter with 15 neon tetras.On paper you would say "yep no probs".Simple.Or is it?

For me the most important part of this example is not the tank size nor is it how many fish.It's the filter or more specifically the filters bio capacity to process organic waste.

Organic waste from dead plant material/fish etc and (the big one) fish food.

In all probability the new keeper is going to overfeed his fish.It's easy to do especially with the feeding advice given on the side of packets.

In effect the keeper is feeding phantom fish which have to be put into the equation.How many phantom fish obviously depends on how much extra food goes in.The keeper could in effect be 'overstocked' with only 15 physical fish in the tank and that's not taking into account other forms of waste.

In my opinion the only way to ascertain the correct stocking level of any given system is dependant on the filters bio load and/or the individual keeper in terms of the level of maintenance the keeper is prepared/able to do.

If the filter cannot process the amount of ammonia or nitrite the system produces then clearly the system is overstocked.The stocking level can easily be increased by way of more media in a larger filter to increase the bio load of the system.(Or try feeding less )

Assuming the bio load is sufficient ,the nitrate level will increase. The rate at which this increases will dictate the level of maintenance required.In a small tank for example with a large filter/bio load and high stock level the nitrate level will obviously rise faster than that with a lower stock level .
This will result in more frequent water changes.If the individual keeper doesn't have the time or even motivation to do higher frequency maintenance then you could argue that this tank is overstocked where as if the keeper relished the extra maintenance and could keep the nitrate within an acceptable parameter then the same tank could be regarded as not being overstocked.

You don't only need to find the systems stocking limit but also your own.

Also whilst establishing your maintenance regime you have got to consider how much the fish will grow.This will obviously increase stocking level in time.If your fish are fully grown then this is no problem.If they are not then allowances have to be made.
This is easy if you think of the phantom fish.If you expect your fish ,to say double in size then double the amount you feed your fish.You only need do this whilst establishing your stock limit.Once established revert to normal feeding knowing your fish can grow in to the space taken by the phantom fish.

My advice - Build your stock slowly and feed accurately whilst monitoring the water closely to establish your tank and your own stocking limit.By monitoring the nitrate you can establish how much water and how often you need to do water changes in order to maintain an acceptable level.I hear people giving alot of conflicting advice on how much water and how often you should do a water change when really it's down to the individual system.

Sorry for the essay and thanks for reading this far.Feel free to criticise.

 

[N0body Of The Goat]

Bearing in mind I'm still waiting for my first caffeine of the day to kick in, by and large I would agree with a lot of what you wrote.

In my early days as a fishkeeper, I started conservatively with a group of Rabbit Snails (now with "ChrisCook") and bought a new group of fish every couple of weeks, providing my test results for ammonia and nitrite were perfect. However, looking back, I got carried away buying fish for my Rio240. As they grew over the summer, the tank looked more and more overstocked (to the extent now I would compare it to a way overstocked Malawi tank), so it was no surprise that one or two more aggressive fish in there got a bit fiesty. Even when I got a great deal on a 5x2x2 in late summer and had to move most of my fish down there because of my breeding Lionhead Cichlids, the tank looked very busy as they grew. Looking back, I may well have lost some fish because of overfeeding, which would have sent nitrate levels through the roof despite my 50% water changes. It was at this point where I think I finally saw the light, depsite nobody commenting on my high stock levels (no doubt not helped by the fact that many of my fish were not that common in the hobby), deciding to rehome some fish for the sake of the fish.

Having been through all this, like others on the forum no doubt, I now tend to edge on the side of caution when it comes to stocking threads. With time comes experience and in such circumstances, seasoned fishkeepers can successfully overstock their tanks(s), but during those early days it is very easy to make mistakes despite having the best of intentions.

 

[fenny666]

seasoned fishkeepers can successfully overstock their tanks(s)

I don't believe you can "successfully overstock".

It contradicts itself.With my method if the system is to be described as overstocked then it falls short in one of two ways as stated above.Either the filter bio load is being exceeded or the keepers maintenance regime isn't sufficient to maintain acceptable water parameters.A third state could also be argued where for example territorial species don't have enough space.

If the system is healthy then in my opinion it cannot be described as overstocked.It is merely stocked within the filters bio load capacity coupled with adequate maintenance.

Too many keepers are advised on stocking levels based on what size tank they have ie inch/gallon or the like.This is just a totally inadequate way of establishing stocking level and yet it is constantly refered to as a good guide.

 

[Llegmore]

While I agree that the capacity of the filter is crucial in considering aquarium stocking, I believe that the size/activity levels of the fish themselves is more important. After all, filters are much more easy to replace than upgrading to a larger tank/re-homing fish. It annoys me when people generalize related to tank size instead of taking into account the needs of the individual fish in terms of territory and even tank depth/water speed. I think the method of extremely gradual stocking really is the only way to do it.

For beginners however, a simple rule is required to provide some kind of guidelines as it's so easy to overstock on your first tank.

I'm not sure that I've made any sense. I partly agree, partly disagree. But I don't think successful overstocking is possible.

 

[fenny666]

It annoys me when people generalize related to tank size instead of taking into account the needs of the individual fish in terms of territory and even tank depth/water speed.

I don't think anyone can argue with that.However I would argue that this is on the topic of suitability as opposed to this topic of establishing stock limits.There is a wealth of information on different fish species for the responsible keeper to ascertain whether or not a fish is suitable for their setup.

For beginners however, a simple rule is required to provide some kind of guidelines as it's so easy to overstock on your first tank.

My point being it's just as easy to overstock using one of these simple rules.They're inadequate.I think a new approach is called for especially when addressing beginners with advice regarding stocking levels.

 

[Llegmore]

"My point being it's just as easy to overstock using one of these simple rules.They're inadequate.I think a new approach is called for especially when addressing beginners with advice regarding stocking levels."


Oh I agree 100%. I just understand the original justification for the inch per litre or whatever it is. A new approach would be great if it could be broadcast to newcomers to the hobby. I admire your commitment.

 

[Mikaila31]

Stocking is part art part science. Everyone stock differently and may methods work. Experience is very important, what one person can do may not work for another. I personally put little emphasis on the filters bio-capacity. However I also run densely planted tanks. Around half of my tanks are unfiltered yet do perfectly fine with a "good" stock. Simply using plants as filtration nitrates generally don't build up as ammonia is taken up by the plants, however I add nitrate to a lot of my tanks to make sure some form of nitrogen is always available. I stock heavy when I can, 15 neons in a 60 liter I would say is light. Even filterless you could manage 30 neons in a 60 liter tank and nitrates would stay stable despite that load. Yet water changes are still done, because there is more to water changes then removing nitrates. I did water changes today in all my tanks and I know nitrates now are higher then before I changed the water.

Overstocked is a vague term. What you might consider overstocked I may not. So a "successfully overstocked tank" is possible weather you want it to be or not. I kept 50+ fish in a 20 gallon high for well over a month all the fish were 1-2" and compatible, all stayed healthy, water was good and maintenance was manageable. I say it was heavily stocked but not overstocked. You probably could of fit many more fish in there before having any problems.

 

[prankster705]

Sum up for everybody who cannot be bothered to read: the easiest way to avoid overstocking is to employ common sense.

For the OP: right, because we all know, that nitrate concentrations below 500ppm have been proven to have adverse effects on fish </sarcasm>.

 

[KISSfn]

I have a phantom fish on order...

 

[cornclose]

I saw some phantom tetra in my LFS yesterday...

 

[minnnt]

Sum up for everybody who cannot be bothered to read: the easiest way to avoid overstocking is to employ common sense.

For the OP: right, because we all know, that nitrate concentrations below 500ppm have been proven to have adverse effects on fish </sarcasm>.

Is it not more a case of under filtering?

I believe 'successfully overstocking' a tank is quite achievable if you're willing to put the time in to the maintenance. A heavily planted tank will also help you achieve this.

 

[tomtomtom1230]

Sum up for everybody who cannot be bothered to read: the easiest way to avoid overstocking is to employ common sense.

For the OP: right, because we all know, that nitrate concentrations below 500ppm have been proven to have adverse effects on fish </sarcasm>.

Is it not more a case of under filtering?

I believe 'successfully overstocking' a tank is quite achievable if you're willing to put the time in to the maintenance. A heavily planted tank will also help you achieve this.

+1

It's achievable but still not ideal, especially for the fish. Again, returning to the idea of using common sense: if it looks over crowded, chances are that it probably is! That's not to say if it looks under crowded then you can stock more fish because there are exceptions and more biologically demanding fish than others out there.

 

[fenny666]

OK

@Mikaila31

Stocking is part art part science. Everyone stock differently and may methods work. Experience is very important, what one person can do may not work for another. I personally put little emphasis on the filters bio-capacity. However I also run densely planted tanks. Around half of my tanks are unfiltered yet do perfectly fine with a "good" stock. Simply using plants as filtration nitrates generally don't build up as ammonia is taken up by the plants, however I add nitrate to a lot of my tanks to make sure some form of nitrogen is always available. I stock heavy when I can, 15 neons in a 60 liter I would say is light. Even filterless you could manage 30 neons in a 60 liter tank and nitrates would stay stable despite that load. Yet water changes are still done, because there is more to water changes then removing nitrates. I did water changes today in all my tanks and I know nitrates now are higher then before I changed the water.

I think you've missed the point of this topic.This is about giving someone who's asking the question of stocking a logical procedure in ascertaining their own stocking limits.

To clarify I should have refered to the bio load as the systems as opposed to the filters exclusively.Apologies or the confusion.Technically I would argue that even your 'filterless tanks' are not filterless at all.If you look at the role of a standard filters bio function water is merely passed over media harbouring colonies of bacteria which process ammonia and nitrite.This is no different to water passing over substrate in your tanks or any other surface in which the bacteria can gain a foot hold.The plants can only utilise a finite amount of ammonia at any one time.The rest is processed by the bacteria in the system.This can be exceeded at which point the system would,of course, be overstocked.Even in the 'filterless' system you describe above a logical procedure as setout previously can be utilised to ascertain a stocking limit.

So a "successfully overstocked tank" is possible weather you want it to be or not.

It's simply not a case of whether I want it to be or not.It's a contradiction.There is a stock limit to any system.If this is exceeded then it is overstocked.If a system is unable to cope with the demands placed upon it then clearly it cannot be described as successful.
What I think you actually mean is," it's possible to successfully heavily stock a tank." Yeah fine.

@Prankster705

Sum up for everybody who cannot be bothered to read: the easiest way to avoid overstocking is to employ common sense.

I think if you told someone to use their common sense when asking about stocking you would probably come across a an arrogant t*&t.Of course ,that would be their opinion not mine.I think your great.Honest.

For the OP: right, because we all know, that nitrate concentrations below 500ppm have been proven to have adverse effects on fish </sarcasm>.

There is enough literature out there to suggest even low levels of nitrate can have adverse effects on fish.And i'm quite sure you can counter this with links to research that suggest otherwise.
Who can be sure?
What I can be sure of is high levels of nitrate are unlikely to be beneficial to fish.Therefore if they are not likely to be found out as being beneficial in high concentrations the right advice would be to err on the side of caution and aim at removing them.That's common sense.

 

[Aqua Tom]

< In my opinion the only way to ascertain the correct stocking level of any given system is dependant on the filters bio load and/or the individual keeper in terms of the level of maintenance the keeper is prepared/able to do. >


[/qoute]

That is exactly my opinion as well.


Tom

 

[N0body Of The Goat]

Perhaps we should be looking at stocking from a more scientific perspective?

Fish food often quotes typical nutritional analysis, including protein.
"x" amount of protein will give "y" amount of ammonia.
"y" amount of ammonia should produce "z" amount of nitrite.
"z" amount of nitrite should produce "a" amount of nitrate.

So we should be able work out how much food we can give our fish to result in a certain amount of nitrate. Given that most fish find nitrate toxic at levels above 300mg/l, if we know how how much nitrate is in the source water and if we could accurately measure how much nitrate is being consumed by plants (note that typical nitrate test kits are extremely inaccurate), "overstocking" would be if each fish cannot get its fair share of food which stops any fish having a sunken belly look and that prevents nitrate reaching toxic levels by doing suitable water changes.

The above also asumes that the filtration is able to keep up with ammonia and nitrite production and not require emergency large water changes.

However, are we all really going to calculate all the above and buy expensive true nitrate level indicators? Is the typical fishkeeper going to be prepared to run an expensive continuous water change system or manually change large percentages of water everyday without fail? I think not...