Backyard Aquaponics
A place to discuss aquaponics

I have been collecting laundry sinks for some time and have them set up on a stand within my dirt vege garden for herbs. My home system is getting closer to happening and I was thinking that these would make great grow beds.

Has anybody had any experience using these? I was wondering if there is any chance of nickel from the troughs contaminating the water and causing fish death as happens with zinc from galv tanks? My initial thoughts are that the nickel is locked into the stainless steel matrix and without some kind of chemical reaction occuring it would have no impact but I don't want to do it if it has been proven to be a problem for others.

Dont know that anyone has tried them Burnsey... if they're stainless... then I don't see them as being a problem... unless they're soldered around the waste plug???? ...

soldering will either be a stainless steel weld, or silver solder.
Silver is a heavy metal, and corrodes easily, yet I reckon that it will be an alloy.
Stainless steel will corrode, so there is something that may get into the water. Can't say what it is though
I doubt the quantities would be a problem no matter what it is, but then I may be wrong.

Burnsy

I'd rub a little roof and gutter seal round where the drain is joined. Check its plastic or stainless where the threads for the drain are.
If things build up a slime coat they are usually ok. Biggest problem I think you'll have is heat loss in winter.

Some are older style with brass drains, no solder or welds though. Is brass a problem? Maybe I should replace the drains with new plastic ones?

Think that would be the go Burnsey... especially the brass ones...

Stainless steel has many grades and I can't tell you much about them. If the stainless is the same grade as urinals, I doubt it, then they should be very suitable as human urine is very corrosive. Perhaps that may give you an idea of a easy test! Exposure over time may be necessary.

Brass on the other hand reacts or corrodes quickly with flexy N, an agricultural nitrogen foliar spray.

i have two stainless growbeds and have had no problems at all. They have been in use since 01/10/08 and i pump 15 mins on the hour 24/7. I have noticed no corrosion i have louisiana irises in them and they are about to flower. I have a plastic disc of polycabonate and it is sealed with roof and gutter. The central disk about 90mm is drilled in the centre 25mm with a 19mm blueline class 12 riser and a 50mm outer bell syphon.

Hello. I used bathtubs and yes, I had nickel leach into the water. And yes, I had lots of problems. I have recently re-done my bathtubs - I lined them with pond liner. This was a doubly whamy because I get rid of the nickle problem, and I also add a layer of insulation - the other thing you'll find with metal growbeds is that they readily transfer heat from the surrounds directly to the water. So your temps swing around a bit.

I neglected to say that my bathtubs were pressed metal with a white enamel. I think it was the fact that the white enamal had worn through in places, and they'd used some kind of nickel product to glue the enamel to the metal.... stainless steel might be fine.

Brass is an alloy of Copper and Zinc, and I don't want either in my system. Steel is iron with carbon and a bunch of other stuff (wikipedia says: manganese, chromium, vanadium, and tungsten.) Stainless steel has more chromium. So really that should be fine.

You can possibly paint the brass stuff with bitumen paint?

Gemmel

If the're not welded or soldered you just unscrew them and they can be replaced with plastic.