Water Change Question

[MOPonder]

How much of the water can I change without having to dechlorinate?

 

[fishin4cars]

Question is, how much chlorine is your water company sending out, or is it chlorimine. It's best to contact you local water company and find out. they are suppose to supply that information free if requested. I would say if you add water slow enough in most cases 10% would be ok. But I do hate to say that as if you happen to leave the water running, that could be disaster, if your water company just treated with a strong dose and you are close to the treatment facility, that could be disaster, You could run your water through a charcoal filter and remove most of the chlorine, or you could run it through ammocarb and get chlorimes out. so there are variables to keep in mind and consider. Good rule of thumb, if your not sure, dechlorinate, It's cheap compared to losing a whole pond of fish.

 

[CometKeith]

Hi MOPonder, I have about the same size pond. I dechlorinate every time by filling buckets and adding declorinator and let them sit for a day. I don't think there is any acceptable level of chlorine and chlorimine. It destroys the fish gills and affects their ability to breathe. You may not see it immediately, but over time it will hurt them.

 

[UT_Bruce]

Frankly I'm not sure what would be a 'safe zone.' How do you know, for instance, if the municipality didn't just do a heavy treatment? Dechlorinators are *very* inexpensive. Not worth the risk. No amount of chlorine/chlorimine is safe for fish.

Also, not dechlorinating impacts your biological filtration, resulting in higher ammonia levels. If feasible, I recommend testing ammonia levels if you are doing more than a 10% water exchange, to be sure the bacteria in your pond are keeping up.

 

[MOPonder]

Thanks for all the replies. I think I'll get some dechlorinator just to be safe.

 

[addy1]

Good idea, hate to lose fish from something we can control. And it is a cheap prevention.

 

[Shdwdrgn]

In my small pond, I had times where the water was pumped out due to a malfunction, and I had to replace about 40% of the total volume. I never knew there were dechlorinators for ponds until recently, so the water was just pumped straight in from my garden hose. The good news is that my fish survived (and some are over 4 years old now), but as said above, this is certainly not recommended! Obviously I have no way of determining if any of the fish suffered long-term damage to their gills, but I try to keep refills down to a low level when I can.

One thing of note (and hopefully ll be corrected if this is wrong)... Chlorine will evaporate out of water within 24 hours (faster if agitated). Chloramine will NOT leave the water without chemical intervention. Your water company will use one or the other, but again, you have to ask them to find out which.

 

[CometKeith]

Shdwdrgn, Here in Chicago they use both. Some people top off their ponds by using a fine mist spray of water from their garden hoses. Supposedly most of the chlorine dissipates in the air when this is done. I have done this at times, but never have added a lot of water this way. Spraying the water is better than just letting it pour in.

 

[UT_Bruce]

Yes, chlorine is quite volatile and evaporates quickly. In fact, you could probably set it out for a day or two and let nature do the work, but I can't officially recommend that as a solution.

We advise our aquaculture customers to pretreat the water before the exchange, for biosecurity purposes. Spikes in ammonia can be better avoided that way, but it requires a fairly large pretreatment tank or lagoon, and most ponders probably don't have that availability (except for the smaller ponds).