User Name Remember Me? Password

Tropical Fish Keeping - Aquarium fish care and resources » Freshwater Fish and Aquariums » Beginner Freshwater Aquarium » Nitrites starting to pick up, when should I do a water change?

 Thread Tools Search this Thread
Nitrites starting to pick up, when should I do a water change?
 01-27-2009, 09:46 AM #31 Tyyrlym I see what you're saying but the analogy has some problems. The first is that the mass of the food in the water is enormous compared to the bacteria. I'm working on getting a piece of data I'm missing, the mass of an average cell, but suffice it to say that even 0.10 ppm of ammonia in an average aquarium is a tremendous amount of available food for a bacteria. Second, my analogy prompts images of a conveyor delivering discrete packets of food at regular intervals so that there is a chance if you remove all the food from the table (a 100% water change) you get the idea that someone might reach for a piece of food and find none before the conveyor brings something else to eat. This isn't the case. Ammonia production in the aquarium is for most part a continuous function. It's more like a conveyor spilling a stream of rice onto a table or a hose spraying water than a conveyor bringing steaks. 1) I reiterate, if the bacteria can consume the excess ammonia in the water then you have a cycled tank. Excess ammonia in the water represents a tremendous excess of food. Most of us are familiar with the cycling graph. Here's the thing, the point where the amount of ammonia in the tank ceases to increase is the moment you have sufficient bacteria present to deal with the ammonia production of the inhabitants of the tank*. Same with nitrite. When the amount stops increasing you have enough to support your tank's inhabitant. The rate the bacteria are consuming the food in the tank is equal to the rate its being created at. Any bacterial growth beyond that represents overpopulation to deal with the excess. 2) Bacteria are consuming pollutants in the tank as quickly as they can at all times. Bacteria aren't like humans, they won't stop eating because they're getting fat or because they're full. They eat everything they possibly can and reproduce as fast as they can. Therefore excess nitrogenous substances in the water represent food that absolutely can not be consumed at the moment by the current bacteria. The bacteria consume the amount of food they can, it doesn't matter how much is present beyond that amount, it makes no difference to the bacteria. 3) The mass of ammonia in a 50 gallon tank with 0.10 ppm ammonia is approximately 30,000,000,000 (30 billion) times more massive than a single bacteria. There are of course far more than just one bacteria in your fish tank but even if you have 3 trillion bacteria in your tank each individual bacteria has 1% of its body mass of excess food available on top of the continual production that is part of the tank. To give some perspective that's like your average man having a hefty steak dinner with all the trimmings on the table in front of him to work on while even more is being brought. Simply put, even at 0.10ppm ammonia (which my API test kit won't even measure accurately and represents a 60% water change when your ammonia is at 0.25ppm) there is still a lot of food for the bacteria in the tank. Based off what I know and what I've seen it is my opinion that water changes during cycling have no negative impact on the length of the cycling process. *Obviously this mostly has to do with fish in cycling which is a far more precise process than fishless cycling. Fishless cycling is easier on fish but not very precise in terms of the size of your bacterial colony at the end. That's why it is CRITICAL that if you fishlessly cycle you take the addition of stock slowly and carefully. You CAN NOT fully stock an aquarium immediately after finishing a fishless cycle. **My math in this is based of an approximation of the mass of a cell, 0.6 picograms. I was unable to locate the mass of a nitrifying bacteria so I took used the mass of an average sized bacteria.
 01-28-2009, 08:54 PM #32 iamntbatman But, as you stated, bacteria and people are very different animals. True, bacteria don't get "full" and stop metabolizing, but they may also have chemical triggers that say, "only reproduce when there is a certain concentration of available food in the environment" that aren't being satisfied if ammonia/nitrite levels are kept as low as possible. We'd have to ask a cell biologist to be sure.
 01-29-2009, 08:16 AM #33 Tyyrlym Yes we would. If there is such a trigger though I am thinking the threshold must be extremely low. So low that we can't detect the ammonia level that remains in the tank. The lowest level of excess I'm suggesting is maybe 0.10 ppm which you'd only see after a very aggressive water change at a 0.25ppm concentration of pollutant. If super low concentrations of pollutant inhibited bacterial growth I'd think we'd see some evidence of it, specifically when cycling with fish. As best I can see however there isn't any significant difference in the time it takes to cycle with fish, doing appropriate water changes, as it does to cycle fishlessly where pollutant concentrations are 20 to fifty times anything you'd see while cycling with fish.

 Similar Threads Thread Thread Starter Forum Replies Last Post catfishtabbi Beginner Freshwater Aquarium 2 07-21-2009 06:30 PM bigk_54 Beginner Freshwater Aquarium 7 02-12-2009 06:49 PM Sj45 Beginner Freshwater Aquarium 5 01-14-2009 04:06 PM eviltuna Tropical Fish Diseases 8 03-05-2008 01:03 AM angel62 Tropical Fish Diseases 5 02-22-2007 03:21 PM

 Thread Tools Search this Thread Search this Thread: Advanced Search

 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Welcome to Tropical Fish Keeping     TFK Announcements     Introduce Yourself         Member Showcase Freshwater Fish and Aquariums     Freshwater and Tropical Fish         Anabantids         Ancient Fish         Betta Fish         Brackish Water         Catfish         Characins         Cichlids         Cyprinids and Atherinids         Invertebrates         Livebearers     Beginner Freshwater Aquarium         Beginner Planted Aquarium         Freshwater Aquarium Equipment     Advanced Freshwater Discussion         Fish Breeding     Tropical Fish Diseases Saltwater Fish and Coral Reef Tanks     Saltwater Fish     Beginner Saltwater Aquariums         Saltwater Aquarium Equipment     Advanced Saltwater Discussion         Coral and Reef Creatures         Nano Reef         Water Chemistry     Saltwater Fish Diseases Other Aquatic Environments     Ponds and Waterfalls     Vivariums and Reptiles Reference Material     Articles         Betta Fish Articles         Brackish Water Articles         Freshwater General Articles         Freshwater Disease Treatment Articles         Freshwater Plants Articles         Miscellaneous Aquarium and Fish Articles         Saltwater General Articles         Saltwater Water Quality Articles     Alphabetical List of Fish Species     Brackish Water Fish Profiles     Freshwater Aquarium Plants Profiles         Floating Plants         Non-substrate Rooted Plants         Stem Plants         Substrate Rooted Plants     Freshwater Fish Profiles         Anabantid Species         Ancient Fish Species         Atherinid Species         Badid Species         Catfish Species         Characid Species         Cichlid Species             Central American             Lake Malawi Haplochromines             Lake Malawi Mbuna             Lake Malawi Peacocks             Lake Tanganyika             Other Cichlids             South American         Cyprinid Species         Livebearer Species         Puffers (Freshwater) Species     Other Freshwater Creatures Profiles     Saltwater Fish Profiles         Acanthuridae (Tangs, Surgeons)         Antennariidae (Frogfish)         Apogonidae (Cardinals)         Balistidae (Triggers)         Blennioidei (Blennies)         Callionymidae (Dragonets)         Chaetodontidae (Butterflies)         Cirrhitidae (Hawkfish)         Ephippidae (Batfish)         Gobiidae (Gobies)         Grammatidae (Basslets)         Haemulidae (Grunts)         Holocentridae (Squirrelfish)         Labridae (Hogfish, Wrasse)         Lophiidae (Anglerfish)         Monacanthidae (Filefish)         Opistognathidae (Jawfish)         Ostraciidae (Boxfish)         Pomacanthidae (Angels)         Pomacentridae (Chromis, Clownfish, Damselfish)         Pseudochromidae (Dottybacks)         Ptereleotridae (Dartfish)         Scorpaenidae (Lionfish, Scorpions)         Serranidae (Anthias, Grouper)         Siganidae (Foxface/Rabbitfish)         Syngnathidae (Pipefish, Seahorses)         Tetraodontidae (Puffers)         Zanclidae (Moorish Idol)     Saltwater Corals Profiles         Soft Coral         SPS Coral         LPS Coral     Other Saltwater Creatures Profiles TFK Resources     DIY Aquarium     Aquarium Products Reviews     Member Submitted Articles     Aquarium Clubs and Events The Tropical Fish Keeping Community     Off Topic Discussions         Other Pets         Dog Forum     Fish Memorials         Other Pet Memorials     Aquarium Photography         Freshwater Journals         Saltwater Journals         Other Aquatic Environments Journals     Diving     TFK.com Suggestions and Feedback     Contest Archives Aquarium Forum Sponsors     Aquaripure

All times are GMT -5. The time now is 08:20 PM.

 Contact Us - Tropical Fish - Privacy Statement - Top