An Aquarist's Journey

[wesleydnunder]

Biofiltration is the process by which bacteria living in our aquaria consume the products of aquatic life. Fish give off wastes just as we do. Anything decaying in the aquarium, from uneaten food to dead plant matter adds to the waste load. The first of these pollutants is ammonia. It is excreted in fish waste and from the gills. If left untreated and/or undiluted, it quickly reaches lethal concentration. There is an aerobic (something that requires oxygen to live) bacteria which consumes ammonia. It lives on surfaces in our aquaria; on the rocks, in the filter, on the glass...basically on every surface that is submerged and gets oxygenated water and food (ammonia) brought to it. When this bacteria consumes ammonia, it gives off nitrite as its by-product. Nitrite is another compound that is deadly to our fish. Thankfully, we have another species of bacteria living alongside the first which consumes nitrite and its by-product is nitrate. Remember earlier in the thread where we discussed nitrate testing, its threshold amount and the dilution of DOCs achieved by partial water changes.


These bacteria are naturally occurring and will colonize the aquarium when sufficient food is available for them. The colonization period can be dreadfully slow if allowed to progress unassisted. It can be accelerated by the addition of bacterial supplements, or the use of pre-colonized filtration media. This process is known as cycling.


The safe stocking density of a given aquarium is largely based on the amount of beneficial bacteria able to grow within the tank. It is further determined by how much maintenance the aquarist is willing to do.


TAKE YOUR TIME!


One of the first mistakes we can make is to immediately load the new aquarium with fish. If the tank is not cycled, we subject the fish to lethal amounts of ammonia and then nitrite as the tank cycles. These poisons stress and can eventually kill the fish. One way to mitigate this is with live plants. Many live aquarium plants will consume ammonia directly as food. Others prefer the end-product, nitrate. By planting a large mass of plants, the ammonia in the tank may never reach harmful levels. The plants often have some of the beneficial bacteria on them and also serve to seed the aquarium with these nitrifying bacteria. So cycling a new tank with fish in it is called a fishy cycle.

[wesleydnunder]

A fishless cycle can be achieved by adding pure ammonia to the tank in measured amounts. I shoot for an ammonia dose of 3 ppm. I measure this quantity using a liquid reagent test kit. I keep a log to track the cycle's progress. I accelerate the cycling process by introducing some bacteria-laden gravel, filter media or driftwood into the tank. A typical cycling period can take anywhere from two to four weeks. It's seldom shorter than two weeks and may last longer. Each day I'll test for ammonia, nitrite and nitrate...then log the values. As ammonia-consuming bacteria grow, I'll see a decrease in ammonia and an increase in nitrite. I'll add ammonia back to the 3 ppm value each day. At a point over the next few days I'll see nitrite value peak and start to drop off. This is accompanied by an increase in nitrate. I keep adding ammonia daily to the 3 ppm level after the tests.

When the cycle gets to the point where ammonia and nitrite read zero and nitrate has increased, I know it's safe to begin adding fish. Hopefully, during this cycling period I've used my time to research what my inhabitants are going to be.


Now what do I do? My tank is cycled and I can start stocking! Slow down...take your time. First I do a large water change to get the nitrates down to around 5 ppm. This gives me a known starting point for later testing. Add a fish or two...test over the next few days. There should be no detectable ammonia or nitrite. Add a couple more fish; repeat testing. During this time, nitrate is rising. When it gets to 20 ppm, time to do a 50% partial. I prefer not to do more than one water change a week, so my additions of fish stop when my nitrate gets to 20 ppm in a week.


This is my typical approach to stocking a basic community tank; tetras, barbs, livebearers, cories, etc. You may have noticed that I didn't once test for ph. This is a subject that many new (and experienced) aquarists obsess over, IMO, needlessly. Research of fish species reveals that they come from X ph or Y ph. So we have to duplicate that, right? Nope. For most aquarium fish, ph is not even a small issue. First, fish have no receptors for ph and have no idea what the ph of their water is. Second, most aquarium fish are farmed in Florida, Texas and elsewhere. The fish farmers aren't bothering about ph. The danios and cichlids are housed in the same water, just like the rest of their species. The majority of the fish we buy are not wild-caught. They come from these farms and have no idea where their ancestors originated. The water they were raised in was perfect, as far as they were concerned.


Don't misunderstand. Some wild-caught fish which come from extreme environments of ph and, more importantly IMO, TDS may need to have their home conditions duplicated...at first. Most, if not all, can be slowly adapted to living in local conditions.

[wesleydnunder]

When we ask questions about stocking on the fish forums, and elsewhere, the answers to the question can be as varied as the number of people responding. They will often suggest (hopefully from a standpoint of personal experience and consideration of the OP's level of experience) fish that they like. Nothing wrong with that. From an experienced hobbyist, it's likely that they've kept the species themselves and can offer some first-hand data to go along with their proposed stocking.


There are some "must-nots" and "musts" which have crept into the hobby over the years which most folks will parrot for lack of a better reason than they read it somewhere on the internet. Examples:

1. For a schooling species, you "must" always keep at least SIX of that species. The thinking behind this reasoning is that schooling species form large schools in nature as a defense mechanism. The constant movement and densely-packed cloud of fish confuses predators and increases an individual's overall chances of surviving to reach the breeding phase of its life. It stands to reason that this behavior is instinctive and follows the species from the wild to the aquarium. These fish seem more "comfortable" with members of their own kind. Thanks to one of OrionGirl's contributions to this thread, we get an idea of how some of our "rules" come into being. But why the number 6? Why not 5...or 7? ...or 20, for that matter? Did anyone ask the fish? Has anyone put a particular schooling species into a very large tank and, starting with one fish, added individual fish of that species and studied the behavior of the school? The reason I specified "very large tank" is that in small aquaria, this rule breaks down. When the borders of the fish's world is measured in inches, virtually none of the natural schooling behavior exists. For any who dispute this, I invite you to don scuba or snorkeling gear and get in the water. Seeing schools of fish numbering in the hundreds or thousands in their natural environment is very enlightening and the contrast between what is witnessed in the lake or ocean vs. what we see in a 20 gallon tank is a stark reminder of how little our artificial worlds imitate nature.


2. You Must Not mix Old World cichlids with New World cichlids. Really? Why not? Well....they come from different environments and have different behaviors and breeding strategies. This will lead to inevitable conflicts! OK...they're cichlids. They're gonna have conflicts, regardless of where their ancestors originated. Cichlids are territorial and have a large number of survival and breeding strategies. Obviously, if you load the aquarium with substrate spawners, there will be disputes over real estate. Housing Malawian lek breeders with south american substrate spawners will lead to territorial conflict at breeding time...but so will keeping different species of lek breeders in the same aquarium. Once again folks, these fish don't know they're not "supposed" to live together. Cichlid purists often get very offended by seeing them mixed.


There are definitely some species which shouldn't be mixed. Some cichlids require care which is so specific to them that other species simply won't thrive. Discus are an example of this. The elevated water temperature that they need to be healthy is too high for most cichlids to endure long-term. Even those species which occupy the same native waters as discus, like angelfish, often don't exist harmoniously with discus in an aquarium because of discus temperament and feeding behavior.

[wesleydnunder]

The best news in all this, IMO, is that with a little thought, some physical work (and not much, really), and the inclination to learn and apply that knowledge, the quality and quantity of life for our captives can exceed that encountered in nature. What?!!

Yup...I think so.

Question: What's the first rule of aquatic habitats in nature?
Answer: Eat or be eaten.

As much as some of us don't like to face the harsher realities of the natural world ( from which many of us set ourselves apart ), the fact is, most of the fish which we keep in the aquarium never reach adulthood in the wild. Most of the babies and juveniles get eaten before that. Of those which do reach maturity, the majority don't live to reproduce. They get eaten before that.

When we stock an aquarium, one of our first considerations is not to mix predators and prey. Sometimes we make mistakes but we learn not to repeat them. While it may be a more natural set-up to house neons and other small tetras with predators, it doesn't keep that stocking long. The neons become expensive snacks.

So in that respect, the fish we keep in our tanks tend to have longer lives than their wild cousins simply because we took a little time to consider their diminutive size and possible consumption by predators before we stocked our aquarium.

[wesleydnunder]

Salt:

Here's another point of contention throughout the hobby which crops up regularly. To salt or not to salt?..and I'm referring to sodium chloride, not minerals intended to boost TDS for certain Rift Lake dwellers.

There is no need to use salt prophylactically in freshwater aquaria...period!

The lfs and big box stores regularly tell customers that "Aquarium Salt" is a necessary additive for the health of their fish. Just how much is needed is never exactly determined. The "Aquarium Salt" sold at the store is simply rock salt milled to a slightly smaller grain size. There is nothing special about it.
The reason that none of the store employees can tell you exactly how much is "necessary" is because the whole concept is made up to sell you something; and since it isn't a necessary additive to your freshwater tank, they can't tell you just how much to add.

The only fish which "need" salt are marine and brackish. Any fish which has evolved in fresh water doesn't need salt added.

Even otherwise knowledgeable aquarists fall into perpetuating this myth.

"It stimulates production of the slime coat." Yep...any irritant does. Fish secrete their slime coat as a natural process of living, just as forcing water past the gills is a natural function. They secrete extra slime whenever they feel an irritant or skin parasite. In a healthy, undiseased fish, stimulating the fish to produce more slime than necessary is needless.

"It prevents diseases." Really? Show me the proof.
Salt can be used in conjunction with elevated water temperature to kill the Ick parasite, but the continued immersion of the fish in elevated salinity won't prevent disease. In fact, salt can stress some fish to the point that they are weakened and thereby more susceptible to disease.

One of my favorite articles on this subject written by Robert T Ricketts, AKA RTR, can be found here: http://theaquariumwiki.com/The_Salt_of_the_Earth

[fishman13218]

Wesley very interesting read. Its really shows the hobby has changed from the early 60s until now. A large tank then was a 29 gallon. Filtration has changed not always for the better. Your corner box filter is still one of the best filters every made.
Keep up the stories.
In the 60s I got a nickel for my Head & Tail lite tetras and two cents for my zebra danios. That money went far as you stated prices.

[imhill]

lucky for me, my grandfather was a seasoned aquarist, and showed 8 year old me how to properly care for my black moor that I won.