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Metals and crustacea
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Author:  steve [ Apr 11th, '06, 15:13 ]
Post subject:  Metals and crustacea
Hi all,

Was reading apost by SueinWA and it reminded me of something.

For anyone having crustacea in their aquaponics setup (marron, yabbie etc) It REALLY important to know that copper is ULTRA poisonous to them.

This mean do not use copper pipes or fittings. Chems like copper sulphate is disasterous to them and even when cleaned out there is enough residue to kill them.

And i think i've read somewhere that bore water high in iron is no good for them either (not to the extent of copper though)


And on the subject (i know its probably obvious) but lead is a big no-no. both for the fish and US! So pretty much all soft solders incase you were going to braze metal fittings.

Silver solders (like i use in the aircon trade) are still no good as they contain cadmium, another heavy metal which is not so nice for us.

You CAN by silver solder specifically made for potable water pipes, which doesn't contain cadmium.

All in all its probably safer (cringe) using PVC and food grade plastics.

Steve
Author:  frosty [ Apr 11th, '06, 16:47 ]
Post subject: 
good advice

but dont forget older PVC contains lead as well

an still not sure about plastics

also found out that some of those square plastic tanks in the metal cage may have bee previously used to contain formaldehyde !!!!

thiking of maybe limestone blocks rendered inside with concrete mix

frosty
Author:  steve [ Apr 11th, '06, 22:20 ]
Post subject: 
Frosty,

Really? lead? I didn't know this.

i know old glazings like in bathtubs used lead

I share your........suspiciousness........ of PVC and plastics, even food grade. I'm a bit of a health nut (not as in excercise :) ) and there is some really disturbing info out on things like phthalates which are used as plasticisers Even food grade plastics.

But hey, i do have the lesser of many evils approach. otherwise i'd be living nude in the forest! :) So if i have to use PVC but get pesticide free veggies then i think its a fair trade at this stage.

I too thought of a concrete type fish tank and grow beds, and they could look REALLY good if done right, almost like a "feature" in the garden, but they are SOOOOO permanent and much more expensive......

Oh while i'm on the topic i'll get this out of my system, Not looking to start anything here because i know how divided the FOR and AGAINST fluoride camps are,
BUT..........Regardless of which side of the fence you sit on a few things are certain, one being that there are definate upper exposure limits for flouride, even the "for" side realises this. Secondly when water evaporates and is topped up it increases the concentration of dissolved solids. Thirdly, the only reason plants are a good source of minerals is because they assimilate them from the soil (water in our case). Join the dots :wink:

People would be astounded at the amount of things that are added to municipal drinking water. I am a little concerned about aquaponics systems becoming "sinks" for high concentrations of different "additives" which are then assimilated by the veggies. topping up with rain water would solve these issues or at the least do periodic water change outs.

Just needed to get that out. all better now 8)

Of course it may all be a conspiracy theory :shock: :D :D :D
Author:  earthbound [ Apr 12th, '06, 12:17 ]
Post subject: 
I should really get my bore water tested to see how good it is for filling my other systems.........

I hope to run my new system on water that is collected from rain that falls on the area of the system only(2.5m x 5.5m), stored in barrels under the growbeds.... I hope it will be enough..
Author:  Cornonthecob [ Apr 12th, '06, 12:19 ]
Post subject: 
Even using rainwater to 'top up' your system will dilute and chemical biuld up? Eventually 'flushing' the system for you.
Author:  steve [ Apr 12th, '06, 15:32 ]
Post subject: 
Yes corny, thats what i was getting at about using the rain water as top up, as it means not having to do water change outs or worry about grid water additives building up :)

I'd hate to shatter the 90% better water usage of aquaponics by wasting water out. I'm going to keep the 1000Lt tanks i've got as a rain storage tank to do top ups, that way once its full its full, and it doesn't matter if we have a dry summer as i'm fairly certain that 1000Lt of top-up water should go a LONG way :)

Steve
Author:  Cornonthecob [ Apr 12th, '06, 15:55 ]
Post subject: 
Yeps, makes sense to me (which is saying something!)...I will move my small poly tank to where my system will be (9000lt).
Author:  frosty [ Apr 12th, '06, 17:19 ]
Post subject: 
HI steve

I am very aware of the problems with additives (poisons ) in scheme water ........I am intolerant to all synthetic chemicals ( almost one of those bubble people :lol: ) and cannot tolerate scheme water at all

we use bore water on our garden and it is free of toxins ( we test it every year ) - but it is high in nitrates and grows a lot of algae........ it is also very high in calcium

we use rainwater in the house so hoping by the time we get our system ready we can fill it with rainwater


pthylates really cause me problems too ........ never store food in plastic

they say polyethylene does not leach pthylates but I am still cautious maybe it even leaches some thing worse :lol:

we have a 320 l stainless steel tank which I think we will use for a fish tank to get started

you have turned me off enamel baths :cry: I had thought they were safe

frosty
Author:  steve [ Apr 12th, '06, 18:06 ]
Post subject: 
Frosty, i think its just the REALLY old enamels that have lead in them.

I think one good yard stick for age is their weight. The really old ones were cast iron heavy as .........well, very heavy :)

The bath tub i picked up for myself a while ago feels more like sheetmetal, very light in comparison.

Hmmm, VERY interesting to hear you call them poisons......not many people do. 8) 8) 8)
you have my user name if you want to PM :)

I'm not even convinced about food grade P/E don't forget the full name for PET is Polyethylene terepthalate. Even blood tested from patients with IV bag drips shows traces. But who knows, nature has a nice way of neutalising somethings i'm hoping that the fish/ammonia/bacteria/micro orgs and such will help. but this is really just a fantasy that make me feel better i think.

Besides like i said minimising risk is better than being ignorant of them :)

once i'm established and harvesting many kilo's of vegies and fish i will make a permanent garden feature of aquaponics........preferably near to the barbie :)

oh, by the way, the bore water sounds GREAT for your system, if its high in calcium then it probably really well buffered against PH swings, and the plant side of the aquaponics RELIES on nitrates, so go for it!

With a bit of experimenting you could probably set up a sub system that takes your bore water, circulates it through a bed of fast growing plant like lettuce and then use it for drinking. The plants will munch up all the nitrates. something to toy with after your aqua setup is all done. Hmmm, now I'M interested in my theory.... can you tell me the nitrate concentration of your bore water in PPM?

Take care

Steve
Author:  earthbound [ Apr 12th, '06, 18:14 ]
Post subject: 
Sounds like you've given up on the idea of the bathtub system then Frosty...?

How is your house dam/pond is it still suffering from algal blooms?
Author:  frosty [ Apr 13th, '06, 07:26 ]
Post subject: 
Hi steve and joel

our bore water has arround 17ppm nitrates ........ we filter our drinking water through a RO - long story steve but we use rainwater in the house but dont drink it because we live near a military training area and have lots of jets flying overhead ........ I know the RO will filter the nitrates but cant be sure it will filter jet fuel residue and possible dioxines

Joel I did think we would give up on bathtubs when steve said enamel has lead but ours isnt that old :? so maybe it is alright

the SS tank seems ideal just wish it was bigger

we have lots of limestone blocks 350 x500 x 110 so these seem a good choice for grow beds ......... poor phil just needs the time to make them !

thinking of putting the plants inside the sunroom with the fish tank just outside with a removable cover

we are still having major algae problems with the big pond - steve we have a 40000 litre liner pond we put in a emergency water storage for firefighting

I have pestered everyone over at PRI about how to solve the algae problem :oops:

Joel suggested aquaponics but we have decided it is too big for us to tackle until we get some experience ....... plus we are not willing to use the amount of power needed to run a big enough pump to recirculate it enough to make any difference

some of the pond places we asked said the problem was the high calcium and some said the high nitrates :? but it grows so thick it stops the pump and all we have been able to do is float cheap black plastic on it to shade it ( yuk ) its been in since jan last year and we have also tried barley straw - the algae grew well ON the straw :lol:

lately have been thinking of trying to harvest it with a big Pondvac and use it for compost ....... we could certainly use the compost because we will still have to grow our spuds in the soil and we are trying to grow grass for the goats

we are totally pesticde free and wont bring in any compost or animal manure unless we know for certain there is no pesticde residues

the gaots are pooing a fast as they can but its not enough :lol: :lol: we have really gutless sandy soil

frosty
Author:  steve [ Apr 13th, '06, 17:26 ]
Post subject: 
Frosty,

my understanding is that RO water filters basically EVERYTHING. could be wrong though.

I'd say for almost a certainty that the algae problems are due to the nitrates. like plants the algae feeds on the nitrate. Phosphate also sends the algae nuts.

You should do a little test frosty, grab a fishtank, fill it with bore water, black out the sides so algae wont grow inside, then plant some plants above it and circ the water through cont. (only a really small pump would be needed for this experiment.) test the nitrates each week and i think you'll find that it will come right down to nothing as the plants have taken them up. If you would drink such water then you could set up a appropriatly sized system with water dripping in at a slow rate, the same rate at which you would use water daily. you could probably get the nitrates down quite low and the water would still be fresh as it being circed and oxygenated and also replaced. Would be interesing if you had the time :) catch is that you would have to seed the system like you would in aquaponics and wait for it to stabilise. (know anyone with a fishtank to steal bacteria from? :) )

Just some interesting concepts for you to think over :)

Ps Many people LOVE the RO water but there is a train of thought that long term consumption may not actually be all that healthy.

It is basically ULTRA pure water. Water the osmosis process is also used by the cells in our body. We need certain sodium, potassium and calcium salt concentrations to function. (as well as many micro minerals) by drinking only RO water, our body releases many salts and minerals to bring things back into osmotic balance. see where i'm going? most of us don't intake enough minerals as it is.

Thats why mineral water or spring water (bore water?) is better. it has dissolved minerals and salts in it.

what are the health concerns with 17PPM nitrates? I've not done research on nitrates in drinking water.

Something to think about.

Steve
Author:  frosty [ Apr 14th, '06, 06:53 ]
Post subject: 
Hi steve

we will try your suggestion with the plants ....we do have a small pump ...... just needs TIME :lol: :lol: I should explain I am useless ( disabled ) I do the planning and talking hubby does the practical stuff.... his to do list is verrrrrrrrrryyyyyyy long :shock:

re RO water ......... I know there can be problems with lack of minerals but because I have chemcial intolerance it seems th best option to avoid the chemicals by using the RO then take mineral supplements

they do say RO filteres everything but recently there was an article about how sailors on ships during Vietnam war who drank desalinated water while in one port ( cant think of the name right now) were contaminated with dioxines ......... only question is were desalinators back then RO ? they are now

but even so knowing that an RO passes the water through a membrane which catches the pollutants I wonder whether it would catch jet fuel residue which is lighter than water ?

so we drink the bore water better safe than sorry

re 17ppm ........ the aussie standard is 50ppm but they are only worried about blue baby syndrome ....... there is evidence than drinking water over 10ppm causes bowel cancer and in the USA the upper limit for municipal water is 10ppm


as you can tell we are very careful about having clean water !!! I only drink water - sometimes straight sometimes in organic herbal tea .......

frosty
Author:  Gary Donaldson [ Apr 14th, '06, 08:00 ]
Post subject:  Fish
Hi Frosty,

At the risk of being accused of proposing Duckweed as the solution to every problem, it may just be the answer to your pond algae problem.

I suggest that you take a look at http://www.fwr.org/wsaa/wsaa151.htm to see what they had to say about using duckweed for algae control. These folks are scientists (rather than enthusiastic amateurs) so I'm inclined to take what they say a bit more seriously than if it was just a pond enthusiast's site (although some of them are good, too).

My understanding of it is that the duckweeds impact algae on two important fronts - they thrive on phosphorus and they compete for sunlight.

In addition, harvested duckweed could be fed to your goats (and other animals) and could also be used as a weed-free compost for your gardens.
Author:  steve [ Apr 14th, '06, 11:08 ]
Post subject: 
frosty,

Gary sounds like he's on the money!

Funny how the simplest solution is often overlooked :) Would still be interseted in the bore water filtration outcome when hubby reaches that page :) on his list .

I remember seeing the same article about the sailors. I assumed the de-salination process used was distilation (actually i'm fairly certian). Which actually concentrates volatile components that have a lowwer boiling point than water. (you probably already know this stuff, but i like to be thourough for the sake of everyone). But i couldn't bet my life on the RO thing.

Sounds like you culd write a book on living chemically free (which is not that easy as i'm sure you can tell every one! )

Oh, buy the way, i did a quick search on the net and found this http://www.leadinspector.com/
seems like you can get these test kits fairly easily, just do a bit more searching to find an aussie seller.

I'd feel really bad if you gave up on the bath tub idea, as i really want to go this way too! I have a bath tub and two small basins waiting, and i think it would look really cool to have plants growing out of basins! :)

Old kitchen sinks would probablygo well too, as they as stainless steel.



Steve
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