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Related FAQs: Treating Tapwater For Brackish Aquarium Use,

Related Article: Frequent Partial Water Changes,

/The Conscientious Marine Aquarist

Treating Tap/Source-water for Brackish Aquarium Use


By Bob Fenner


Most municipalities disinfect their drinking water with chlorine or chloramine. These chemicals are deadly toxic to disease-causing microbes, unsightly, distasteful algae, and unfortunately, our desired aquatic life! Present practices result in a highly variable tap-product; one that should be monitored and must be dealt with, either by storage/aeration over an extended period, conscientious treatment, or very slow and/or limited water change regimens.

This article will familiarize you with the whys of these sanitizers, your options in dealing with them, and symptomatology & therapy for poisoned livestock. Hey, I'll even give you my version of "the best way" (according to the Fishman) to render tap water usable. Ho-boy!

Why Do We Have To Deal With This Stuff Anyway?:

Always a good question. Answer: Because it's there. Water intended for human consumption; drinking, bathing, washing, what-have-you is rendered biologically zippo (that is, nothing living in it) by semi-unselectively poisoning it with materials that are supposedly not very toxic to us.

As the story goes, there was/is a high positive correlation with the blending of free chlorine with organics, present more and more in source waters, resulting in compounds termed tri-halo-methanes (spelling mine). Tap water in the U.S.A. used to be primarily treated with chlorine as a gas, or liquid (principally as the bleaching agent, sodium hypochlorite, aka hypochlorous acid). Due to the aforementioned problem, linking colonic cancers with tri-halo-methanes, the fed. EPA saw fit to pass laws supplanting free-chlorine-liberating means of potable water sanitizing with the less noxious (as far as colonic cancers go) but more persistent chloramines. But, dear reader, please allow me a short digression:

There are still places where this magazine reaches, like Britain and Japan, where chlorine is still in vogue, and even (gasp!) Western Europe, and some commune(ities) utilize the commie-subterfuge-itself, flourine(!). And so, let us have a slight review of the ole High School level qualitative chemistry, shall we? As you'll recall, in the most popular presentation of the primary building blocks of the universe (atoms), there is an arrangement of these elements in a Periodic Table, or Chart.

By definition, the vertical columns in the periodic chart of elements are called Families of elements. Ostensibly, all members of a given family share alike chemistries on the basis of kindred arrangements of electron-cloud configurations. The column immediately adjacent to the far-right family of noble gases, is termed the halogens (note the similarity of halo above and halogen here). Geez, anyway what I'm trying to get to here is that all members of the halogen family (halogenated be thy name?) act (poison) the same. Fluorine, Chlorine, Bromine, Iodine and Astatine. Anywho all these atom-types are very reactive, wanting only one more electron to fill out their outer electron cloud, but that's another story (thank goodness). They all will kill your fish, invert.s, algae, live-rock, whatever you have, in sufficient concentration. On with this story.

Chlorine (Cl2) bound up with ammonia (nominally NH3) we'll call chloramine. This critter is responsible for almost as much captive mortality as hobbyist-generated-booboos! No small feat. And the reason(s) why? Let's make that a seperate article, okay? Suffice it to write here that: 1) Chloramine is present in toxic quantities in virtually/actually all city water supplies, 2) It takes a good week or so to "dissipate" by "setting", "aeration", "hopeful wishing", or other such means, or 3) Can be neutralized by various store-bought or home-made chemical conditioners, some only-effective with concurrent contactor filtrants (e.g. carbons, zeolites) to remove resultant ammonia. But most all wanna-be advanced-aquarist-types know some version of this extended-greatest-fish-poisoning-story-ever-told.

Basically, know this, the water district types are not your best fishy buddies. For various reasonings, they fool with the water, very occasionally yielding a more and more toxic product that you must remain vigilantly suspicious of.

Mode Of Action:

Chlorine, Chloramine, Fluorine compounds et al. are hemolytic in their action, splitting up blood cells. Additionally, in sufficient concentration, the actual gill membranes will dissolve in their presence. Both these reduce respiratory capacity (no duh!)

What's A Pet-Fish Type To Do? First and foremost, be aware! How else are you going to "get by" in the world, let alone optimize your opportunities? Next, determine whether you're going the intensive versus extensive (lazy) mode. In the former, extend your senses and get a test kit for chlorine/chloramine. How 'bout an advertisement/schpeil here? Okay! Aquarium Pharmaceuticals has a nice inexpensive liquid-reagent variety, Hach and LaMotte have some nicer units for the hoi polloi, and there are even electronic types for the lottery-winning, ultra-tech-ee. The extensive/lazy approach is to MAKE FREQUENT, SMALL WATER CHANGES (boy, that's bright on the old word processor), say 10-15% at weekly/twice-monthly intervals, gambling on absorption, complexing of tap sanitizers with "what's in your system". 3) The last and generally least desirable, but necessary to discuss means, are directly chemical in nature. You know their names, the sundry new/tap water conditioners. Let's not name-names directly here, but do let us make a general classification scheme/discussion on the basis of apparent activity, and some letting-on concerning ingredients...

A) Dechlorinators: These are the tried and true (sodium) thiosulfate, aka hypo, or hyposulfite compounds. Yes, this is the same stuff you may be familiar with in terms of photographic developing chemicals for (surprise!) removing free chlorine to eliminate interaction with silver... More on this real soon.

B) Dechloraminators: Here I mean one's that "really" work, that is, that take care of both chlorine and ammonia. These typically involve poly-vinyl compounds. This is a big hint!

C) Pea Suede Oh (pseudo), read that as phony "Dechloraminators". Yes, there are products, some quite popular, that profess to "remove chloramine in "one-step". A vital clue here is their formalin/formaldehyde smell. What a scam! These products "work" by 1) poisoning your livestock such that it produces slime and other materials in response to the formalin and thus precludes chlorine/chloramine from entering their bodies, and 2) as a placebo, albeit toxic one, where no treatment was necessary.

Don't believe me? Get a test kit and do the simple experiment. How do these companies stay in business? People buy their stuff out of ignorance. Don't be ignorant.

Too Late, I Already Blew It:

What can you do, if your livestock are poisoned by these sanitizers. You have to act quick, seconds, to minutes, to (rarely) hours. Depending on the source and degree of the problem, do (in order of possibility):

1) Move your livestock to a non-toxic environment. Keep your eye constantly on your charges, especially for bullying.

2) Treat the water! You twit! With items listed in 3 & 4 below.

3) A real dechloraminator, and definitely not with a phony one. More mucus production and hemolytic activity by formalin poisoning will only exacerbate pushing your critters over the edge. Watch the dosage. Do not overtreat!

4) Engage filtrants (carbons, zeolites, appropriate resins) to remove the source of the problem.

5) Flush the whole mess and start over again. Oh sorry, just kidding. Other Sources of These Noxious Chemicals:

Principally from "cleaning" ornaments and tanks with "chlorine bleaches" and household cleaners' fumes and aerosols making their way into your tanks. What you can do to avoid these despicable circumstances should be obvious, and I don't get paid by the word, but here's a gander at poisoning prophylaxis: A) Rinse the dickens out of whatever cleaning stuff you're using, air-dry, use a cheapy bio-assay, break-down and buy/use a test kit, will you? 2) Be careful, don't use ammoniated or chlorine-containing and releasing compounds around your system, geez. 3) Flush the whole mess, no, not this again!

How To Save Your Livestock, Your Sanity, & Your Pocketbook:

My real advice is really to just do frequent partial water changes and not sweat it, but, in reality, if you're changing a lot of water, I would suggest what I and our service company do:

Batch process your water with, I mean cheap, home-made hypo solution purchased from a chemical/lab or photo supply outlet and either pump/drain your supply water over a chemical filtrant (cited above) to remove the remaining ammonia. Sodium thiosulfate at about two pounds dissolved in a total volume of one gallon, used at one-two drops per tap gallon is about right. There are folks who sell this stuff through the magazines, if you won't get off your duff and check out your local "yellow pages".

And the Very Best Method!? None At All: Premixing/Storing Brackish Water

The simplest, most assured way of making sure sanitizers, metals (that can be settled/complexed), excess gasses... are removed from solution ahead of using synthetic salt mixes is to pre-mix and store them for a week or so ahead of use. This is best accomplished by way of buying and dedicating "Fish Tank Only" gear to the purpose. A new (my favorite are the Rubbermaid (tm) Brute) trash can and lid (to keep little hands and stuff out) maybe with their spiffy dolly to roll around... a pump (like a powerhead, but with a nozzle for attaching a bit of flexible tubing to ease moving the water to your system(s)... and possibly a thermostatic heater (make sure and unplug this when doing additions)... and your trusty hydrometer... 

     By allowing the new water to mix and circulate, many things are done... chlorine/amine are liberated, perhaps excess gas, metals... and the various soluble and not so components of your salt mix are able to complete solubilize ahead of use.     

Let's Wrap This Thing Up Already:

Chlorine and chloramine poisoning are significant causes of livestock loss. The sources of these sanitizers and there testing, removal and therapeutic treatment has been surveyed. If you won't invest in and use a test kit, be chary of massive water changing, or at least use "real" dechloraminators. Thanks!

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