Backyard Aquaponics
A place to discuss aquaponics

Why not put in a stand?

BF - To answer you question I have delved into all sorts of small scale moulding (silcone/fibreglass), model making, model rocket cones (carbon fibre), played around with some kevlar (didn't stop the bullet ), model boats etc etc. It is so handy for prototyping, the elastosil moulding products make it a breeze to make a crap load of small items. Made carbon fibre gunstocks and grips for miles-tag laser skirmish guns.

Not really related to AP, but the skills I learn't from it are invaluable.

Too true TC-
To set the record straight I am married to the grand daughter of the guy that brought it to Perth,
anyone who know the history of FG in the west will prolly know me or the Fam.

I'm not sure I want to know anymore. I have 5 fibreglass aquaculture tanks, 1 of Murray's fibreglass tanks and 4 of his fibreglass beds. This is the stuff that will make up my big system (though I have an excess of tanks and once I know what I don't need I'll probably offload the extras).

I have no idea what sort of resin etc is used in them. They have a marine flow-coat (white) - not sure if this is added pre or post mold release.

Might ask Murray for some more info - but I'm fairly confident that they are safe (have to be).

VB- That is the best asumption!
I am sure that if no fibre loss is happening all is good!
Looks like my answer has put the xxxx's up a few ppl.
Not my intention.
But yes ask xx without nominating the right one.
aside- I will do up a sample pack for you VB of the soycrete.

Thanks C1 - I appreciate it.

Re the fibreglass, there are no exposed fibres on any of my tanks - at least not on the inside that is. At some point I'll communicate with you to find out what is allegedly the safest form of flowcoat, because I may get some to touch up some exposed areas on the lips of my tanks and other fibreglass gear (not really any exposure to the fish water - but better to be safe than sorry).

I guess it may also be wise in a few years time for me to empty the beds of gravel to ensure that there has been no significant wear and tear to the flow-coat.

Yr on the pace VB.

Seeing as how this subject has come up a couple of times, I rang Ajay Fibreglass Industries at Alstonville.

They have been supplying the aquaculture industry with fibreglass tanks for many years including the vast majority of the tanks at both the Fisheries sites at Pt Stevens NSW and Bribie Island QLD.

Mr. John Fleming ( the managing director) himself rang me back and discussed the matter, asked what I was going to do etc.... and said he would send some info down to me which duely arrived.

Unfortunately while he sent several product brouchures and price lists he didn't include any reference material relating to the issue of fibreglass.

However this is what he said. From the notes I made, (and maybe you can interpret C1), he maintained that (obviously) they had been making fibreglass tanks for aquaculture for years and that he was unaware of any problems....

With the proviso that the tanks must be manufactured from Isothphalic (sp) resins not Orthothphalic (sp) resins.....

Must use NPG Gel and Flow coats.....

Must use Vinyl Ester resins for the "tie layer"....

Must NOT use MEKP, STYRENE in the manufacturing process....

Should not use "Marine" grade Gel coats.....

As I say, he didn't include any technical information regarding the subject so I can't give anyone any definitive references to support any arguement one way or another...

What do you interpret his comments to mean C1??

Regardless of the above VB, my gut feel is this.... if it's not affecting your fish then (given a six month grow out rate) it probably wont affect you...

Consider that through evaporation and any water changes that you're probably changing out 100% of your water over a period of xx months...

Any possible contaminants would have to be fairly miniscule I'd think....

Then there's also the possible "filtering" effect of the gravel growbeds....

Again with the speed of the flood and drain and general speed of plant growth, I'd be fairly happy that any detremental affects would be minimal....

Rupert - my concern with leaching of chemicals has always been that because it is a closed system - then they will concentrate over time. They would not theoretically be lost through evaporation.

Having said that - although I have no scientific basis for it - I knda think that other than for heavy metals, the ecosystem that AP creates is likely to take care of small amounts of chemicals. Some of the work that has been done with fungi and stuff to clean up contaminated areas is amazing.

I also agree that fish are fairly sensitive and any real bad shit would probably have an adverse affect on them. [Edit: mind you, fish have of course been shown to accumulate heavy metals, but maybe metals and chemicals are different for the purpose of this situation]. All the same - I'd like to be fully confident of the safety of my system.

The frustrating part VB is that I can't give you any definitive answers.... because the more I research it the less answers I get....

Certainly "burning" fibreglass products are hazardous and toxic..... and there are definite risks associated with handling and working with resins and solvents..... similarly there are obvious risks associated with fumes and airbourne particles... possibilities of asthma, nausea and skin allergies

Certainly some of the base chemical compounds are "phenols" and various "amines"... and Styrene and MEKP are all fairly nasty .....

ON THERE OWN ... but combined, cured...... there's just nothing readily available thats says ... yes or no....

The bloke was obviously busy, but I'll ring him back to thank him for the product sheets and prices and ask if he can point me to any research...

Take your point about a closed system VB.... was meaning that water loss/replacement to the system, even though closed loop, and the amount of time for fish grow out might possibly minimise or negate any "cumulative" effect of any leaching

Then as you say there's a natural filtration and conversion process taking place in our growbeds which isn't fully understood....

It's not too far a step to suggest that a bacterial process that breaksdown/converts ammoina and nitrite/nitrate products/processes couldn't in some way also convert "amine/amide" based traces from other sources.

Thanks Rup, for doing the research. (Not that I privately haven't)
Ortho is a general purpose resin, not for containment of liquid
though it can be used for such!
What will happen is that over time osmosis will ocur.
Osmosis is the ingress of the liquid, in this case water.

Like I said if you PM me I will discuss with you over the phone.
Very complex I can phone out for free if you don't like std rates.

thanks a heap for the data guys.

the way i look at it is this.

it is likely that long term exposure to fibres and resins can cause long term damage especially if you happen to be sensitive to such substances. its probably like smoking cigarettes. some people smoke their whole lives and live til there 100. some people smoke only a short term and develop cancer. the difference is that while cigarettes only lead to an empty wallet, the fibreglass and resin are going to produce fresh fish, crustaceans, fruit, veg, herbs and more. i suspect the health benefits from this produce will out way the negatives of short term exposure to fibre and resin. if you had a poor diet and were unhealthy i feel you would probably be effected more by these substances. i believe that organic produce has a way to purge out toxins from the body. if you are already full of toxins then there will just be further build up.

these are just theories though. not enough research has been done yet but time will tell. best to be on the safe side though.