Tropical Fish Keeping banner

1 - 20 of 37 Posts

·
Registered
Joined
·
2,010 Posts
Discussion Starter #1
OK, so it's a bottle.

I keep seeing all the talk about surface area and biofilms (more often called bacterial colonies here) and how they need to be maximized in order to be able to handle the ammonia created by the fish that we keep. A while back I did some calculations to compare the surface area of sand and gravel substrates of various grain sizes and various filter media and determined that the filter, as far as biological filtration is concerned, was a small part of the equation.This is sort of an experiment to see if even all that area is really needed in the first place.


Being a planted tank person I believe that plants are the easiest and best option but understand that not everyone wants to deal with plants for a variety of reasons. As a result, I skipped the whole tank cycling process. I understand that it still happens in the background even with a ton of plants and that it effectively becomes a dual system. I have since decided that I want to try creating a stand alone nitrogen cycle and do it in the simplest controlled environment possible, mainly to see what it is all about. I'm even using fish food that I would have otherwise thrown out... so it is a very cheap experiment.


Interestingly, there are more surface square inches of glass per gallon of water in my bottle than in my rectangular tank by a factor of 5 so I consider that compensates for the lack of filter and substrate to a certain degree.

I am using tap water at room temperature, fish food as an ammonia source with no substrate, plants, filter or circulation other than me moving it every once in awhile. I am aiming to keep the ammonia no higher than 1ppm. Water testing will be once per 24 hour period for ammonia and nitrites and nitrates only periodically. I am not concerned with nitrates and I really don’t want to have to do all that shaking anyway. The prime indicators of cycle completion are really the ammonia and nitrites dropping to zero with new ammonia added.

Tuesday I set up the jar, filled it with water and added four medium sized sinking pellets... probably too much for a small volume, but I can adjust as needed. Yesterday I tested ammonia at 0.25ppm. Right on cue. Nitrites were zero or at least unmeasurable with the test kit.

Jeff.
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #2
Day 4

Tested ammonia, 1.0 ppm. I have not added any more food yet, obviously no need. I did a 2/3 water change to bring the concentration down to .3 ppm estimated as I want to keep it below the 1.0 ppm threshold. Easiest water change ever, pour out what I want to change and run the tap to fill it, all water changes should be so easy.

Nitrites are at 0.125 ppm if I have to put a number on it. The colour is sort of halfway between 0 and 0.25ppm. The water change reduced these as well, which is fine.

I still haven't tested for nitrates. The issue is that nitrates are produced 1 for 1 from ammonia. At least that is what I am lead to understand so the nitrate colour scale is 0, 5, 10, 20 etc, it is not nearly so sensitive as the ammonia and nitrite tests. Once I see them appear as non zero I can probably test every 5 days and get a better idea of their buildup.

The water appears a little murky but not terribly cloudy or anything. If it were a much larger volume perhaps the murky would be more apparent as there would be more of it to try to look through.

Jeff.
 

·
Registered
Joined
·
116 Posts
Sounds interesting, you said you are using tap water, won't that inhibit the cycle? Chloramines doesn't evaporate...

Oh yeah, how big is the bottle?

It sounds like a cool experiment, keep us updated!
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #4
I'm on a well. Even so, I doubt that even the chloramine would inhibit the cycle being established by much. Even so, if I were doing this with city water I would still treat with prime anyway.

Bottle is about 1/3 of a gallon.

I hear that small water volumes are harder to get a cycle going, I doubt that now that I have done the math. It may be harder to keep it balanced with fish, I expect, as it takes far less ammonia to spike the concentration than in a larger volume but I have no plan to put fish in this.

Jeff.
 

·
Registered
Joined
·
2,477 Posts
I would be more interested in seeing how it worked using regular ammonium hydroxide. I expect it to work either way but decomposing fish food relies on a lot more bacteria then just then just ammonia to nitrate conversion. So I guess the question is what exactly are you trying to figure out? Nitrosomas and nitrospira/nitrobacter bacteria convert ammonia to nitrate and that its all. Breaking down fish food is going to rely on many other bacteria to produce the ammonia. I would wonder about oxygen levels when you have little more then surface diffusion going on and are trying for high bacterial activity. Low oxygen is going to slow the bacteria down.

I'm not sure why you are focused on surface area? Nitrogen fixing bacteria can colonize as heavily or sparsely as needed usually. I've personally never worried about surface area apart from the surface area of the water. Where aerobic nitrogen fixers colonize depends on a lot more then just surface area. I am one of those that believes the filter is often a large source of the nitrogen fixing bacteria in the tank, but that does depend on how both the tank and filter are setup. They certainly don't need the filter to colonize an aquarium, but the conditions in the filter are usually more ideal.
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #6
Seeing as I had ammonia within 24 hours of putting the fish food in the water, the initial bacterial activity is next to negligible in the whole picture, so the difference between using a pure ammonia source and fish food is one of neatness and maybe accuracy for the sole sake of accuracy. I can add food to bring the levels up or not change the water so soon but the 1ppm ammonia has been proven to be a threshold over which the nitrite oxidizers are inhibited from doing what they do best. I would have liked to do a side by side to prove this extends the cycle timeline but researchers have already done this.

Knowing how much food I added to bring the ammonia to 1ppm in an uncycled container lets me know how to judge the cycled container in testing afterwards to see how effective the biofilms are in this nitrogen cycle.

The surface area is not really of interest, just the fact that there is no additional surface area involved other than the glass container itself. I read about biological filter media and hold the opinion that they are not nearly as effective as advertised in many cases (although they don't really make claims that they are, just intimate that they are by their nature) and are not really needed in the first place. So rather than prove them not effective, it's easier to prove them unnecessary and therefore a waste of time and money... even if only to me.

I expect that not many will like my attitude toward well known and trusted brand name manufacturers' biological media products but that is my nature, to look under the marketing.

Also, I asked a couple of months ago for some timelines from people and their cycle setups and didn't receive any feedback. I just needed to establish what a timeline would be for my own curiosity, and I would have done it for that reason alone... it's just more fun to have other reasons as well.

Jeff.
 

·
Registered
Joined
·
2,477 Posts
well I certainly agree biological media is a waste. Its not something I would bother picking to use in my filters. The only bio media I have is stuff that came with filters or I that bought 6 years ago. I do view them more as a marketing gimmick. I have some ceramic noodles(rena or fluval brand) that have been in constant use for 6 years. Yet when you hit one of them with a hammer the inside is still nice and dry and as white as when I bought them. I have never seen anyone prove they function any better then standard sponges/floss. I've always preferred good sponges and floss over any other media. I keep wanting to buy a bunch of poret foam but keep talking myself out of it =/
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #8
I just did the ceramic noodle test a week or two ago and found the same thing... although I intentionally broke it expecting that result.

Poret foam, interesting cell structure. It just looks like custom cut foam unless you look closer but is it that much better? It reminds me of the filter foam used in small engine carburation.

Jeff.
 

·
Registered
Joined
·
2,477 Posts
Poret foam is said to be better but I expect that could be questionable, since it is simply foam. Its actually not that easy to find customizable open cell foam for the aquarium. A number of filters use/sell just one pore size when it comes to sponges/foam, it may work for some, but filters run a whole lot better with various sizes. Any filter running 10,20,30ppi foam, and floss is going to filter and polish water very well both biologically and mechanically. Poret foam is more rigid then any other foam I have come across, that is the most noticeable difference to me anyway. When ever someone wants a hamburger mattenfilter it is the go to foam for that. But far as I know both the foam and that filter design came from Germany so its not that surprising. I mainly want it just so I know pore size and it is sold in easy customizable blocks or sheets. Its not like foam goes bad or needs replacing regularly. Its pretty affordable if you have lots of tanks, I just don't.... yet. I do have a couple of unused canister filters I got really cheap that need media and I would rather not buy the over priced pads sold for them. I have a habit of collecting equipment:roll:. The US seller of poret foam moved close to me recently. Which means I will probably end up buying some if they start coming to some of the local club events around here, one way to get out of shipping costs lol.
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #10
Day 7

Interesting test results yesterday. Ammonia at 1ppm, it seems to be peaking at 1 each day. Nitrites have dropped to zero but I haven't tested yet today to see if they are steady zero. I was going to test nitrates every five days but maybe I'll add one in today to see if there are any yet.

It's too early to tell if this is the telltale nitrite drop. I should dump the water altogether and add fresh food, I haven't had to add any yet as the ammonia levels have remained high... in fact I could have done with less food to start with an brought it up gradually to eliminate some of the water changes... not that they are hard.

I might start another bottle to produce ammonia laden water to add to the first jar so I can better fast the ammonia is dealt with. Easier to see a static 1ppm concentration and time the disappearance than try to judge based on constantly decaying food. I would sooner do this than go buy ammonia for no other reason than I don't have time to go looking for a pure source but the pure source may have been more revealing of what is going on.

Jeff.
 

·
Registered
Joined
·
5,139 Posts
Seeing as I had ammonia within 24 hours of putting the fish food in the water, the initial bacterial activity is next to negligible in the whole picture, so the difference between using a pure ammonia source and fish food is one of neatness and maybe accuracy for the sole sake of accuracy. I can add food to bring the levels up or not change the water so soon but the 1ppm ammonia has been proven to be a threshold over which the nitrite oxidizers are inhibited from doing what they do best. I would have liked to do a side by side to prove this extends the cycle timeline but researchers have already done this.

Knowing how much food I added to bring the ammonia to 1ppm in an uncycled container lets me know how to judge the cycled container in testing afterwards to see how effective the biofilms are in this nitrogen cycle.

The surface area is not really of interest, just the fact that there is no additional surface area involved other than the glass container itself. I read about biological filter media and hold the opinion that they are not nearly as effective as advertised in many cases (although they don't really make claims that they are, just intimate that they are by their nature) and are not really needed in the first place. So rather than prove them not effective, it's easier to prove them unnecessary and therefore a waste of time and money... even if only to me.

I expect that not many will like my attitude toward well known and trusted brand name manufacturers' biological media products but that is my nature, to look under the marketing.

Also, I asked a couple of months ago for some timelines from people and their cycle setups and didn't receive any feedback. I just needed to establish what a timeline would be for my own curiosity, and I would have done it for that reason alone... it's just more fun to have other reasons as well.

Jeff.
I agree with you regarding biological media and planted aquaria.(plant's can be excellent biological filter's)
Can't say this for tank's sans plant's,holding number's of large fish (cichlid's).
Mechanical media in these tank's, clog's quickly and is harder for water to flow through.(more frequent cleaning).IMHO
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #12
Day 8

Ammonia back to 1ppm, nitrite still at zero so that test was not a fluke. Nitrates at non-zero.

The highest the nitrites tested at was 0.25ppm. If I assume that that concentration is what is being oxidized in a 24hour period and the ratio of ammonia to nitrite to nitrate is a 1:1:1 (I don't know but is think that it may be) then it might be safe to say that the nitrates could be as high as 1ppm due to the four days since the first nitrite appearance and they seem to be oxidized on the fly now. The colour scale is not that demarced to tell if non-zero is 1 or less. I'll know better in a few days based on where it rises to and how fast.

The 1:1:1 would also suggest that the ammonia is being oxidized at the same rate as the nitrates are being produced so my ammonia production is still outstripping the jars bio capacity which is apparent by the daily rise to 1ppm anyway.

Jeff.
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #13
Day 9

I guess I could have called the thread "The Seven Day Cycle". Nitrites are still zero after three days. I haven't retested nitrates yet but I expect that they are slowly climbing.

The only reason that the ammonia levels keep returning to 1ppm is due to the food still in the bottle decomposing. I guess I was a little heavy handed with the food considering the size of the jar. No real issue as I was able to keep the ammonia concentration at or below 1ppm.

I measured 1ppm again today and I removed the fish food by just running the water through a coffee filter. I then returned the ammonia laden water back to the jar to see how long it takes to drop to zero. If it does, the cycle is established and has been for the last three days.

More testing to come.

Jeff.
 

·
Registered
Joined
·
5,201 Posts
I'm surprised that you chose fish food for your experiment. Ammonia would have been a better control.


Sent from Petguide.com App
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #15
I'm surprised that you chose fish food for your experiment. Ammonia would have been a better control.


Sent from Petguide.com App
True, but I had fish food on hand and didn't feel like going looking for a pure ammonia source. I was curious about the food decomposition as well, I mention that below.

I haven't posted anything new as not much has changed.

So, still in process, day 31.

I did test the water 5 days ago and the ammonia was down to 0.5ppm from 1ppm on it's own. The issue is that I used fish food to bring the ammonia up and water changes to keep it at 1ppm or less. I only ever added food once and when I filtered it out using the coffee filter after the cycle was established, I could not get it "clean" so there were still minute particles decomposing which has been driving the ammonia production even since the filtration. If I had used pure ammonia I could have just stopped adding it.

I was curious to see how the food decomposed over time and saw that ammonia was present within 24 hours, 0.25 ppm, and in 4 days it reached 1ppm and required water changes to keep it at or below 1ppm thereafter... until I filtered the food out.

Today it is slightly lower, somewhat under 0.5ppm and the nitrates are between 0 and 5ppm, in the lower end of the range. I also did a sniff test, I stopped doing that pretty early on as the smell was pretty nasty. Today there is no bad odour, in fact there is really no discernable odour at all and I have a pretty sensitive sniffer. I won't be doing a taste test anytime soon, duckweed is one thing.

Once it is down to zero on it's own (all the food is decomposed) I will add another ammonia source to test it... it might still be fish food but it would be representative of what might be expected if there were some teenie tiny fish in there.

I could just dump it and refill with clean water and it would serve the same purpose but I wanted to see if the jar would still handle the overload that is in there now. I also wanted to leave it this way to see how much the nitrate concentration rises without water changes... although there may be no empirical measure (#ppm ammonia in = #ppm nitrate out) it will serve to demonstrate the system efficacy. Actually, I would like that measure as I think it is a 1:1 ratio but I don't know for certain. With no plants or fish I could measure this well enough... I may will look for some pure ammonia after all so I can do just that.

Jeff.
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #16
Day 45. About 6 and a half weeks.

Ammonia is zero... Not sure when it bottomed exactly as I haven't tested in 14 days.

Nitrate is 5ppm

There has been no water added or changed since day 28 when the ammonia stopped climbing.

I am going to replace the water this weekend and add a very small amount of fish food to see if the system can stay ahead of a very small load. I may see about picking up some ammonia if I get a chance then I can change out the water to specifically test controlled ammonia concentrations now that the cycle is fully established and proven to be able to handle some ammonia on an ongoing basis.

I am at the point of considering that the nitrifying bio films that develop in a tank will grow to meet the load we introduce with the fish and associated wastes without the need to try to provide additional surface areas for them to grow on. Considering that, by default, we already provide a substrate, various ornaments, rocks, driftwood and filters with some porous media as well as some form of circulation to make the whole system more efficient, there really is no need to be concerned about adding any bio film friendly media.

I am of the opinion that the various bio friendly mediums (bio balls, ceramics and what not) do not actually do what they claim any better than classic foam and floss while some don't do any of what they claim, and I still stand by that, but it is easier to be able to say that they are not needed in the first place.

Jeff.
 

·
Registered
Joined
·
2,010 Posts
Discussion Starter #17
Two weeks ago I replaced the water in the jug with fresh well water and added 13 small food pellets. I tested every few days for ammonia and never saw anything more than a very slight blush in the tube... What Imight refer to as "non-zero" which could as easily be attributed to the lighting as an actual ammonia reading. Today I tested and used outdoor natural light and it is definitely zero. So are the nitrites. Theres not much sense in testing for nitrates yet as the scale has much larger graduations and is likely to test very low.

The jug has a nice sustainable nitrogen cycle. I even did the sniff test and there is not only no unpleasant odour, but there is no odour at all. The pellets are all still in there as there is no help from fish or snails to break them down quicker.

Today I added one more pellet and will continue to add one every day or two to drive the ammonia production higher to see if I can force the cycle to become overloaded. One additional pellet is an approximate 8% increase in source material.

Jeff.
 

·
Registered
Joined
·
166 Posts
JDM, the results of this experiment would be really interesting to the people in the betta forums. It's very commonly believed that tanks smaller than 2.5 gallons can't hold a cycle and that therefore constant water changes (even as much as daily) are needed--there's even a sticky over there about it. If you wanted to post over there about your results, I think a lot of people would find it really helpful.
 

·
Registered
Joined
·
5,201 Posts
JDM, the results of this experiment would be really interesting to the people in the betta forums. It's very commonly believed that tanks smaller than 2.5 gallons can't hold a cycle and that therefore constant water changes (even as much as daily) are needed--there's even a sticky over there about it. If you wanted to post over there about your results, I think a lot of people would find it really helpful.
I think a lot of people would just blindly argue with it.... But I agree, I think many of the betta people need more exposure to fish keeping and a better understanding of the nitrogen cycle.


Sent from Petguide.com App
 

·
Registered
Joined
·
166 Posts
I'm just curious about what the results of this mean for a small tank. How often would one do water changes, then, in say a one-gallon tank, if it can hold a cycle?
 
1 - 20 of 37 Posts
Top