Backyard Aquaponics
A place to discuss aquaponics

Excellent news I see the pool water is looking nice and clear!

Pool has returned to its swamoy state. Its an awful mess and the kids would love to have their mates over for a swim but its just not going to happen, I won't let it, I'm worried about the health and very embarrassed.

There is no barley in Sydney, I will buy some as soon as I see it. I have ordered a bottle of liquid barley from the US at considerable expense. while I am waiting for that to be shipped, I investigated some professionals.

Many of which won't return my calls or emails. There is one bloke that can install a biofilter type thing, it is a one day job apparently and is situated in the deep end of the pool. but unfortunately wants $15000. Wow.

So I am doing more research. There is a mob you can buy a DIY ebook for $80, but I have calculated the media you need for my size pool and it will cost in excess of $10 000.

I am investigating whether or not to position a large stainless tray on the floor outside the pool (size would be 20% of SA of the pool) and whack some waterlillies in there and have pool water flow into and out of this area. I think its the go but don't want to throw too much more money at this project with no guaranteed outcome.

Apparently my problem may not be the nitrates but the phosphates. I do know that my neighbour used to use superphosphate on his paddock and that with the fishfood would explain the mess I'm in.

There are phosphate binders you can get from pool shops, but I believe it is substituting one chemical for another.

I haven't measured my phosphate levels yet but will do when I get a kit and report findings. Meanwhile I need to investigate how deep I need my bio-add on to be and figure out which plants are the biggest phosphate suckers.

I may be able to get a stainless tub to house the plants at cost price, so I'm hoping that is is nowhere near the $15 000 mark.

I tell you I'm in the wrong business....

Have you tried here? http://stephenbros.com.au/

What sort of media are you calculating the cost at?

If you're using clay balls, it'd get expensive. But plain gravel works fantastically. It's heavy, but I can get a tonne for $60, delivered. And that was enough for my 2.4m x 1.2m bed.

Personally, I'd just set up as many beds as humanly possible with gravel, and start pumping. Just make sure your supports over the pool are sufficient, otherwise, well, it wouldn't be fun. A few thick I beams should be sufficient.

Biofilters are easy to make. plenty of info on youtube etc.

the media can be almost any inert product with lots of surface area.

I made one using bird netting as the media, just put it in something and pump water and air into the bottom.

Hi Gordon I looked at their website but thought it was a bit pricey, $100 plus postage for 20kg straw (would that be one bale? So I would need 2. The concentrate I bought claims to treat 500 000l of water.

I don't think any amount of media will reduce an algae problem it have I got this wrong? My thinking is that the bacteria that live on the SA will convert nitrogenous waste to nitrate, but will do nothing to remove phosphate and hence stop algal growth.

I'm seriously considering putting in a length of growbed along one side of the pool, 10m x 500 mm which will leave me with 500 mm walking room between it and the pool, making it tricky but do-able. I already have the pump, all I need is the bed and grow media. But this again won't stop my algae. However that combined with my barley straw, I may be on to a winner.

I will wait for my holy grail barley straw before I make any rash changes.

But in the meantime let me know if I'm wrong.

Also thinking about changing the filter sand over, someone mentioned to use shell grit? But I thought that would raise pH which algal love.

Ouch, yes they are way too expensive- I didn't check their prices.

I agree, I can't see how having a whole pile of media is going to help at all, unless you have plants in it to use up the P and N, which is what the algae is currently doing. A big growbed with lots of plants should go a fair way towards solving the problem though. How long before the barley juice arrives?

It was dispatched last week so I'm hoping this week. I'm happy to have another growbed! It would definitely help but not eliminate my problem. Quite looking forward to it actually but I think I'm nearing divorce lol

Have you considered building an algae scrubber? They are often used to remove phosphates and nitrogen from polluted waterways.
In theory they are very simple. Water is pumped onto a flat, rough surface creating a thin sheet of water flat provides ideal conditions for algal growth. because the algae on the scrubber has better access to light, co2, o2 and the nutrients in the water it out competes the algae growing in the water.
nutrients are taken out of the system by scrapping the algae off the and scrubber and throwing it in the compost or where ever.
Anyway that's just one idea, and would probably be only part of the solution. I hope you get it all sorted eventually.

Hey that's a fantastic idea! Could then use to feed the chooks. I am kind of doing a similar thing with duckweed but my duckweed isn't growing. Algae scrubber is a fantastic example of the problem being the solution. Will google now.

Remember those sheets of polyester insulation I suggested some time back? They make perfect algal scrubbers, and are performing as just that in my system right now. They have nice thick smooth matts of algae on them. I'll grab a pic shortly.

Ok I look forward to it. Thanks Gordon. Are you able to clean and reuse them?

A thick smooth patch of very dark green algae growing on the polyester insulation matting. I have these under most of my GB water outlets, and the system water is crystal clear. They work as filters initially, but at this stage not much water flows through the fibre, it just acts as a substrate for algal colonies.

It does mostly wash out with a high pressure hose jet, so you can reuse them. You could even scrape some off I guess, it is about 5mm thick. I usually move them around a bit so eventually the whole surface becomes covered, then turn them over and grow algae on the other side until it becomes covered too.

You can use goe-tex (I think its called) material for placing over soak drains you can get it from Bunnings in the drainage area
you can also get barley juice from the pool area in Bunnings not very big amounts though

the more the water moves the less the algae

Gotex might be the next plan. Nitrates still 0, pool green as ever one week after I added recommended amount of barley grass extract. Added more yesterday still no change. Pool pump, biofilters and UV light running 24/7.

Soo over winter I plan to excavate a grow bed alongside the pool. Only thing is if my nitrates are 0 and the algae is loving it, what's a growbed going to achieve? Which plants will win the nitrate war, the vegies or the algae? With a nitrate of 0, will any plants grow?

So much science, so little time...