How long does dechlorinator remain active

[seangee]

There is an unusually high amount of organic waste in the pond this year, possibly as a result of the unusual weather. Yesterday I did an impromptu 80% water change. Since I had a bottle of Seachem Prime that won't get used (I have switched my tanks to RO) I decided to use that. I dosed for the volume of the entire pond. About 4 hours into the re-filling I went out to dinner and reduced the hosepipe to a trickle. I turned it back onto full when I came in. By the time I turned the tap off it was about 8 hours since I had put the Prime in.

This morning I turned the tap back on for the last few litres (probably about 5% of the volume). By the time the pond was full it was about 16 hours since I put the Prime in. I'm curious as to whether it was still reducing the chlorine at this time.

 

[FishGuest5123]

I’d add a little more to be safe.

 

[Byron]

This is a question I would put directly to Seachem if I were you. They have a contact email on their website and are very good at responding within hours usually.

I do know that in correspondence with me on the effectiveness of Prime with respect to detoxifying ammonia, nitrite and nitrate, they stated that Prime would be effective at this for 24-36 hours, after which the ammonia/nitrite/nitrate will revert back to the toxic form if still present. Also we discussed heavy metals and adding Flourish Comprehensive with/after Prime since Prime detoxifies heavy metals, and their advice was that after 24 hours the fertilizer could be added (and not at the same time or immediately after Prime) and it would not likely be nullified by Prime, though 36 hours would be certain.

 

[Guppylover3x]

I’d add a little more to be safe.

I agree with Deanasue.

I always add more to be on the safe side. It doesn’t do any harm to the fish.

Good luck!

 

[seangee]

I’d add a little more to be safe.

Well its small for a pond but at 7000 litres it would be adding a lot more

Prime with respect to detoxifying ammonia, nitrite and nitrate

The question was idle curiosity about the de-chlorination. My water supply uses free chorine rather than chloramine and ammonia is not an issue. I know that Seachem do recommend a lower dosage of their Safe product for ponds than aquaria because of the relatively larger surface area, and I used the aquarium dosage. In my case the chlorine would gas out way faster than in a tank because (when empty) the hose drops the water in from a height of 1 1/2 metres. At the other end the filter return drops by a full metre (again when empty). I also have 6 airstones running so while filling there is a good deal of surface agitation going on

 

[Back in the fold]

I would like to know the science behind how these chemicals really work. I don't understand how one chemical kills another and then disappears. Sounds like voodoo science. I'm from the Dr. Innes era where we aged our water. I still do.

 

[seangee]

I would like to know the science behind how these chemicals really work. I don't understand how one chemical kills another and then disappears. Sounds like voodoo science. I'm from the Dr. Innes era where we aged our water. I still do.

Hmmm - 7000 litres is a lot of water to store though.

That's all very well when your tap water is treated with free chlorine. A lot of water companies use chloramine because its more cost effective and "lasts longer". Unfortunately aging doesn't make it go away.