Backyard Aquaponics
A place to discuss aquaponics

After much discussion here over time, the other day when I was getting chlorine from the pool shop I asked them about getting in some sodium thiosulphate (which I know is supplied by one of the major pool chem mobs in QLd called Focus).

The guy points to a shelf where there is a lone 250gram container of sodium thiosulphate, Lo-Chlor brand, so I bought it. Probably a bit more expensive than buying in bulk, but was not a lot ($12.95).

It says that 985g/kg of it is sodium thiosulphate, don't know what the rest is, but probably nothing to worry about I'd think - what do you guys thing?

As for dosage, it says that 50grams will lower chlorine by 1ppm in a 50,000 litre pool. This will let me work out dosage rate for tap water, provided I can get an idea of the chlorine content of tap water :-/.

The other big issue/question is whether this stuff removes (converts) chloramine as well as chlorine - does anybody know?

This link is useful

http://aqua-culture.blogspot.com/2007/0 ... phate.html

And this link contains recipe for making homemade neutraliser from Sodium Thiosulphate. Shelf life 6 months - which means I don't need to mix up the chrytals every time

http://users.vcnet.com/rrenshaw/finalnet.html

An interesting snippet in this particular document is that chloramine can be formed by adding untreated chlorinated water to a tank that contains ammonia

Gassing off the chlorine not an option. I have a couple of large tubs with air stones going 24/7 and take water from these. Even started to water the pot plants from here as well because they seem to grow better without the chlorine in it.

That is a good option for chlorine, but will not work for chloramine.

PS - not sure why I've finally got around to gettign some chrystals instead of buying the expensive stuff from the shops, given that my 22,500 litre rainwater tank is now installed and half full and within a couple of weeks I expect to have installed my 18,000 litre tank as well - which will be on the shed and only metres from the AP system.

Is a good topic all the same though.

I used to work at an aquaculture farm and we used chlorine to sterilize water. They we outgassed with air and used sodium thio. Sun and outgassing works well if left for a day or 2 but sodium thio is instant.

Yea after running around today finally found a shop that had the stuff, I think I got the same stuff (but mine was $9.95 ) Lo Chlor brand?

I found it hard to find a good tester for chlorine ( I need one that reads .25 ppm? I dunno lower the better?)
Couldn't source a chloramine test kit at all, is there such thing? Maybe it shows up on the chlorine test and I should delete this line.

Oh and sorry VB for thinking you were steve for a bit maybe steve made a post about this also, plus you guys are the same species of fish

Can't remember the dude who first spoke about the method, was the guy that had a lot of aquarium experience - think he might have spat the dummy over something and has not been back since.

Steve did speak about it as well and was looking at sourcing some at one point.

As for the cost - I got mine at the pool shop where I get my chlorine, so did not running aroung at all - I wonder how much you spent in petrol (or phone calls) finding the stuff . We might be even.

I've had a dirt garden for a number of years and I lay soaker hoses on the tops of the rows after the plants come up and it is set on a water timer. But I clearly noted that tap water during the dry spells, the plants stay alive and grow a little but rainwater is what really makes them grow. I even added a liquid fertilizer attachment to it and the rain water still out performs. I knew the chlorinated water wasn't good for the plants as its purpose is to stop algea/plant growth in water. It didn't dawn on me to collect rainwater for this purpose because it is of our rainfall totals here but it can be very unpredictable. Some years very wet and some years very dry. Dechlorinated tap water is a good idea. Thanks for shareing I will check my pool supply.

I bought a bag, maybe a gallon worth, of Sodium thiosulfate from http://www.thechemistryconnection.com for maybe $10/US. It seems to be working.
I found them on Ebay (US)

Mine doesn't seem to be working, however I just dump the crystals into the water without mixing first.
My chlorine test could be faulty, I use DPD tablets.

I hope mine is working - can't tell without testing, which I've not done at all. I made up a bottle of solution which I use. Using chrystals is definitely not a wise thing to do - unless you were doing the chlorine removal in a separate place and adding the water at a later time. Event ehn there would want to be good agitation I reckon.

I use vitamin C (sodium ascorbate) at a rate of 6 grams per 100 litres to neutralise chlorine. How many others use this method and is it as safe and reliable as it seems?