Aquaholic's First System

[RupertofOZ]

Aquaholic... simply... they float, regardless of attempts to "weigh" them down...

And when they do... they also begin flying around with any breeze... and/or getting into your siphons/pumps etc...

I tried weighing them down with gravel, floating hydroton on top etc... and found that the other media just ended up sinking through to the bottom... and the beads just going everywhere...

[Murray]

Mate, bite-the-bullet, get the gravel.
You will soon forget what you paid when you are enjoying the wonderful veggies and fish dinners.

As a general point....not directed at you 'holic,

I am often fascinated as to why we will go out and spend a couple of thousand dollars on a 2 mtr wide TV just to watch the same garbage but in extra big, or waste 10k on a useless jet ski, or stitch ourselves up for a 40k 4x4 because the girl in the add said it was sexy, but when it comes to possibly the most important investment.....a food production system, we want everything for nothing....
Food has little or no value to us because we can get it for next to nothing on almost every street corner.... The stuff on the street corner and in the s/market is garbage and is killing the nation, but it is cheap....

Yes, we want better food, but we still want it for nothing or as close to nothing as we can get.

Wierd eh !! The workings of the human mind....who can know it ?

[aquaholic]

G'day Murray,
Yep, I'll be using gravel for the first bed. But I still wouldn't mind experimenting using beads/gravel in the second bed, unless you blokes can talk me out of it Cost is not so much the issue, it's getting the materials to the site.

Rupert,
If I could find a suitable barrier to separate the gravel and beads, as well as hold the beads in place, do you think that would work? Obviously the barrier would have to be something that allowed water and plant roots to pass through. Landscape fabric? 5mm mesh?

[bigdaddy]

Hi Holic,

I reckon you will have one massive mess if you use beads, but, as it seems you are similar to me and would like to give it a go anyhooo....

What about some lump or natural charcoal (NOTHING ELSE, NO OTHER FORM OF CHARCOAL WILL SUFFICE) down the bottom then some enviromat on top then, if you have too, beads on top of that then some stainless steel flywire on top of your beads then some clay balls on top of that...I don't know where the roots of the plants will go so that may not work....Just thinking out loud...

One other thing, I'm not sure of the capacity of the beads (Surface area) to breed the beneficial bacteria...

I like Yabbies suggestion of looking at bringing a pallet of clay balls in....they are considerably lighter....Dunno if you can or not...but it would be worthwhile checking that idea out...

Cheers.

[RupertofOZ]

.

Rupert,
If I could find a suitable barrier to separate the gravel and beads, as well as hold the beads in place, do you think that would work? Obviously the barrier would have to be something that allowed water and plant roots to pass through. Landscape fabric? 5mm mesh?

Tried that as well Aquaholic... the constant up and down fluctuation of the water... due to the flood & drain.... just eventually resulted in the edges. or sections of the fabric and/or other media folding or moving... releasing the beads...

There is also the factor that BigDaddy mentioned.... the question as to the surface area for bacterial nitrification...

Bite the bullet as Murray says... although given your logistically constraints... I'd say go for the hydroton...

[Yabbies4me]

IMO the only way to stop the styrofoam beads from creating an absolute mess and possibly also blocking things up would be to make a sack from shadecloth or weed mat that was sewn up, completely containing the beads.

However, if they get out it will get messy. I was landscaping the backyard of a house we bought a few years back and dug up a few bags of styrofoam beads that the previous owner had burried, all of which ruptured to some degree, releasing thousands of beads that flew around to all corners of the backyard. The only way I could effectively pick them up was to wait a few days then walk around my yard with the hoover and vacuum them up where they had collected in corners, along the fence line etc. Seven years later when we moved, even after having completely landscaped and brick paved the backyard, I was still finding beads... they were a major PITA.

I also believe that 200mm of the beads in a grow bed, even contained, would float and repeatedly lift the the top 100mm of gravel and plants during each F&D cycle.
.

[aquaholic]

Thanks everyone, that's exactly the kind of info I'm looking for.

Ok, so the barrier needs to be more rigid and secure than I originally thought. Perhaps something like 10mm mesh and screwed down at the edges, with 20mm gravel on top. Using bags is also a great idea, just need them to be made from something roots can penetrate easily. But it would certainly make clean up and disposal much simpler.

It's also a good point Yabbies4me raises about the upward force of the beads. For 300 litres of poly beads in water the upward force is going to be almost 200kg. So the weight of the gravel has to balance this.

I've also seen bio filters for RAS that use poly beads as the media, so I'm hoping that this will translate to the growbed.

Cheers

PS Hydroton will definitely be the go for the first growbed.

[llewelynj]

In my view, to hold beads down you will have to get stainless steel mesh - which costs a packet, as it doesn't breakdown or cause any havoc with fish. If you do go this way, this mesh will have to be 5mm or smaller as beads collapse under pressure and then will move up through your GB, causing headaches (i think we all have had bean bags as kids).
here in cairns for 10mm mesh im looking at $270 m2. So if your doing this because you want to try it... and then later on you my have to pull down whole GB to clean out and replace grow medium...

also so think about the roots of plants. so product you get to hold beads down will have to allow them through, be strong and longevous. otherwise this could be an expensive and back breaking experiment.

maybe you should look at another product.

[aquaholic]

G'day llewelynj,

I was thinking (and I could be wrong here) that it doesn't matter so much if the beads can rise up through the mesh, as long as the gravel can't fall through. So if I used 10mm mesh and 20mm gravel it should work out. Also, this should allow enough gaps for plant roots to grow through.

Bunnings has 10mm plastic garden mesh for about $40 for 5m2. Whilst it's not as rigid a stainless mesh, it may not necessarily have to be as the beads should take most of the weight.

Cheers

[bobbyd]

Visit an empire such as 3M and get a giant piece of scotch brite the size of your grow bed and simply put 100mm of gravel on top of that, maybe.