well i never have any problems using straight tap water here in the uk, i never have and see it as a waste of money for me and my cichlids... obviously lots will shoot me down for this but im just being honest. i do a 50% water change every week and my fish are fine some in there are over 3 years old. ive kept an oscar for 7 years before using this method... de-clorinator is propergander spread the word!-) lol.... or maybe i just have good tap water.
I don't mean to come across crass...all I am shooting down is your blanket statement about conditioner being unecessary for everyone, just because you haven't had any immediate casualties by not using it yourself. OP is in Canada, not the UK. If OP were your next door neighbor, then there's less of a problem because your experience and advice is relevant to him. But making a general statement about water conditioner being a waste of time and money without knowing what is added to his water in Canada is off base.
It sounds like your water is treated with chlorine, which can burn off quickly enough to not kill your fish, especially so if you are running a drip system. But the levels of chlorine in your tap fluctuates. If you happen to do a large scale water change when chlorine levels have spiked, your fish could be in trouble.
If you are using Seachem Safe at $25 that treats 200,000 Gallons, treating 100 gallons of water only cost $0.0125 US$ (yes, that's just a little over a penny to treat 100G). Treating 1,000G will only cost you $0.125. That's a really cheap insurance policy. During heat waves, some water treatment plants may raise the levels of chlorine added during their treatment process so you are taking a gamble by not treating your water. Considering treating the water is so cheap, I'll take the insurance.
This is a great read on the subject:
http://www.cs.duke.edu/~narten/faq/water-treatment.html
I use municipal tap water in my aquarium. What do I need to know?
Most people use tap water in their tanks; it is easiest (and cheapest) to use. Unfortunately (for aquarists), local water companies add chemicals to the water to make it safe to drink (e.g., by adding chlorine or chloramine to kill bacteria). More recently, concern about water flowing through (older) lead pipes has caused some water utilities to add pH-raising chemicals to the water (lead dissolves less readily in alkaline water). Consequently, tap water must be specially treated before it can safely be used in fish tanks.
Another potential problem to be aware of concerns variability in the chemical properties of your water supply over time (e.g., month-to-month). Some water districts don't have enough water themselves, forcing them to purchase additional water from neighboring water districts in times of shortages. If this water has a different hardness (for example), your tap water's hardness will vary as well.
As a common example, high bacteria levels are more of a problem in summer than winter, especially in warmer climates. Consequently, it is not uncommon for water companies to use more chlorine in summer months to keep bacteria in check. Even such factors as local weather can have an impact; heavy rains may cause the hardness of your water supply to decrease, as local reservoirs fill.
In general, chlorine and chloramine are the two additives that cause the most problems. Note that these two substances are VERY DIFFERENT! Be sure you know what is in your tap water and treat appropriately.
What do I need to know about chlorine?
In the US, EPA guidelines require that tap water at any faucet contain a minimal chlorine concentration of .2 ppm, and stringently limits the concentration of bacteria (which may require more than .2 ppm chlorine to keep in check). Because chlorine breaks down over time, the chlorine concentration of the water that comes out of your tap will be lower than that put in at water plant. Thus, the exact concentration at your faucet depends on how far you are from the water plant, how long it takes the water to travel from the water plant to your house, how much chlorine is initially added, etc.
Chlorine at high concentrations is toxic to fish; at lower concentrations, it stresses fish by damaging their gills. Concentrations of as little as .2-.3 ppm kill most fish fairly rapidly. To prevent stress, concentrations as low as 0.003 ppm may be required. Fortunately, chlorine can easily be removed from water by the chemical sodium thiosulfate, readily available at fish stores under various brands. Sodium thiosulfate neutralizes chlorine instantly. Note that there are many "water treatment" products that are advertised as "making tap water safe". Read labels carefully. Inevitably, the ones that neutralize chlorine all contain sodium thiosulfate, plus other substances that may or may not be useful. If your water only contains chlorine (as opposed to chloramine), sodium thiosulfate is all you need. The most cost-effective treatments use only 1 drop per gallon of water. Most other water treatments are much more expensive in the long-term; they may require a teaspoon of treatment (or more) per gallon!
Chlorine is relatively unstable in water, escaping to the atmosphere on its own. Water left in a bucket (or tank) with adequate water circulation (e.g. filter or airstone) will be free of chlorine in 24 hours or less.
Many netters (justarn, they are talking about you!) report that they perform partial water changes without ever treating their tap water to remove chlorine. Keep in mind that even though fish show no APPARENT ill-effect from untreated water, that doesn't mean that the chlorine isn't stressing your fish. How much stress depends on how much chlorine is introduced to the tank, which depends on many factors (including the percentage of new water added). Because chlorine removers are so cheap (pennies per usage), the insurance they provide should not be passed up.
What do I need to know about chloramine?
One problem with using chlorine to treat water is that it breaks down relatively quickly. Another concern with the use of chlorine is that it can combine with certain organics (that may or may not be present in your water) forming trihalomethanes, a family of carcinogens. Consequently, many water companies have switched from using chlorine to using chloramine. Chloramine, a compound containing both chlorine and ammonia, is much more stable than chlorine.
Chloramine poses two significant headaches for aquarists. First, chlorine-neutralizing chemicals such as sodium thiosulfate only neutralize the chlorine portion of chloramine, neglecting an even bigger problem: deadly ammonia. The consequences can be devastating to fish. Although a tank's biological filter will (eventually) convert the ammonia to nitrate, the time it takes to do so may be longer than what your fish can tolerate.
The second problem relates to water changes. One of the primary reasons for doing regular water changes is to remove nitrates that build up. If your replacement tap water contains ammonia, you'll be putting nitrogen right back into your tank and it will be impossible to reduce the nitrates below the concentration in your tap water. Fortunately, tap water concentrations are relatively low (1 or 2 ppm); you are more likely to have a much higher concentration of nitrate in your tank.
Chloramine can be safely neutralized through such products as Amquel, which neutralize both the ammonia and chlorine portions of the chloramine molecules. The neutralized ammonia will still be converted to nitrates via a biological filter.
Another method for neutralizing chloramine is to age it while simultaneously performing biological filtration. For example, get an appropriately-sized (plastic) garbage can, fill it with tap water, dechlorinate it with sodium thiosulfate, and then connect an established biological filter to it. Just as in your tank, the bio filter will convert the ammonia to nitrate, after which it can safely be added to your tank. Note: you must add sodium thiosulfate to neutralize the chlorine; otherwise, the chloramine will kill the bacteria in your biological filter.
Alternatively, the ammonia can removed by filtering the water through zeolite or carbon before adding it to your tank. [Note: folks report mixed success with this. If you have concrete (positive or negative) experience to report, please notify the FAQ maintainers.
Are there any other water impurities that I should be aware of?
Quite possibly. In addition to the additives described above (chlorine & chloramine), municipal water may (or may not!) contain other elements that the aquarist may need to know about about. Water in some locations actually contains nitrates. In some places, water contains elevated concentrations of phosphates (1 ppm or more). High phosphate has been linked to algae problems, and a comprehensive algae control strategy may require removing phosphates. High levels of iron (1 ppm or more) have also been linked to thread algae. Consult the algae section of this FAQ for more details.
How do I find out just what my local water company is adding to the water?
The quick answer is to ask someone who knows. A local fish store (if they reside in the same water district as you do) should be able to tell you. Alternatively, call your local water utility. Ask to speak with the "water chemist". Tell them you are an aquarist and want to know about the pH, GH, and KH of your water, as well as how much the water characteristics vary from month to month. Finally, (in the US) if you really want details, have them send you a copy of the periodic water report they are required to generate for the EPA. It contains a detailed listing of exactly what your water contains and in what concentrations (e.g., iron, nitrates, phosphates, etc.). By law, the report is available for public inspection.
tank is now all disassembled and new flooring going in. I have to rebuild the sand as it is all water shot now also. I had a timer on the topper/drip to only have the water on for 30 min at a time, but that was till enough to create a huge mess.
