Overstocked?

Tetrabetta12

Ok, i did a 50% water change Friday night. Should i go ahead and do another water change tomorrow night?

Byron

Sure. Three or four days apart is fine.

Just so you understand the reasoning behind what we have been suggesting. Tank space has two major factors to fish.

First is the physical space needed for the particular species to be "itself," and until there is a bigger tank not much can be done about this; but small fish obviously need less space, so this works for the interim. As the fish mature though, this aspect becomes more and more important.

Second factor is the water quality. Fish release substances into the water. Some are rather obvious, such as waste and ammonia (latter via respiration at the gills). But there are also things like urine (which is basically stale water), pheromones and allomones. Pheromones affect the fish itself (it can inhibit growth significantly) and others in the species (inhibit growth, inhibit or increase spawning, feeding, etc). Allomones affect other species, and may cause severe stress. These are chemical substance es that can warn other fish of aggression even if no actual physical threat occurs. Which is why one has to be careful when combining species, to ensure they are compatible.

Water changes address the water quality issue, by diluting these substances and thus reducing stress on the fish. When tanks are small, more frequent water changes keep more of these substances out of the water, and the fish are thus healthier and will grow more naturally. Fry for example grow larger faster the more water changes are done. Discus breeders often do 2 or 3 90% water changes every day. And this allows them to maintain more fry in the tanks, up to a certain point of course.

Hope that is of help.

Byron.

Tetrabetta12

Ok thanks Byron, im running by the pet store today and getting a 10 gallon tank and filter. I think that will be a lot better for them until i can get my hands on a 50 gallon. Im going to cycle the water out of the previous tank because im going to let the 10 gallon cycle for a day or two before i add the tetras into it. :)

Byron

This is good, but you may have a misconception about cycling that i will explain.

The bacteria you need to deal with ammonia and nitrite live on surfaces in what we term a biofilm. They do not live in water, so moving "old" water does not assist this, but may in fact transfer other stuff you don't want, like more ammonia, pathogens, etc.

Setting up a new tank needs time for the cycle to establish. This can be sped up a couple of ways. Easiest is with live plants, fast growing ones, and floating plants are ideal here. Second, you can "seed" the tank with bacteria. This can be done by using the filter from an existing tank on the new tank (without any rinsing/washing/new media, etc), or moving solid objects into the new tank from an existing tank as these will have some bacteria on them. Wood, rock, substrate. Or you can use a bacterial supplement, which is live bacteria in a bottle, and there are a couple of reliable products. Dr.Tim's One and Only, Tetra's SafeStart, and Seachem's Stability are three I would use.

Until the new 10g is cycled somehow, do not move the fish into it from the 5g, this might well finish them fast.

Byron.

Tetrabetta12

Ok, how long will it take for the tank to naturally cycle without any chemicals?

Byron

Many factors affect cycling, and it can be anywhere from a couple days to several weeks. Remember, you are still cycling the present 5g tank. Read my article on bacteria:
Bacteria in the Freshwater Aquarium

Ammonia and nitrite are both highly toxic to all life forms [except the bacteria that use them, obviously] and even at low levels the fish can be seriously affected internally, and down the road may develop various health issues and disease due to the weakening of their immune systems, and usually early (premature) death. The stress alone caused by ammonia and nitrite is serious, not to mention internal damage.

Tetrabetta12

Ok ill read your article! :) I also heard that putting small amounts for fish flakes in the tank will give the bacteria something to grow on. Is that true?

Byron

Yes. We call this fishless cycling, because we are introducing ammonia (via the decomposition of the fish food by various bacteria) by means other that fish, and the Nitrosomonas and then Nitrospira bacteria will establish once ammonia is present.

Tetrabetta12

Alright, so my setup as of tomorrow will be the 10 gallon tank with gravel, plants, etc. It will have a 5-15 gallon filter on it and no heater since its only going to be a tetra tank and i know they like colder water. Im not going to use any chemicals to cycle it, but want to do a cycle with fish. Should i just add the 8 tetras to the 10 gallon tank since they school and i don't want to keep them separated for long?

Byron

Will there be live plants, and some fast growing ones like stem plants or better yet floating? Adding fish to an uncycled 10g is going to severly hurt the fish without live plants.