Any ideas on filtering a swimming pool with a "grow bed"?

[Louise]

I'm considering buying my kids one of those round swimming pools that stand on top of your lawn. But I don't like the idea of adding chlorine and other pool chemicals to it.

So I was thinking about natural swimming ponds that I've read about (beautiful link here: http://www.inspirationgreen.com/natural-pools-swimming-ponds.html). Now, I don't really have the time and energy to make a beautiful thing like that at the moment, more urgent matters call on my attention. However, I was thinking something along these lines:

I have a black IBC tank. I could raise it up on pallets so its bottom outflow is just above the rim of the pool. The IBC gets the top cut off, and is then filled with media, and some filtering plants such as sedges, irises, water mint etc. Pool water is pumped continuously up to the top of the IBC, and flows back through the bottom outflow to the pool.

Recommendations say equal surface area of plant zone to pool zone. This would not be the case here, I'm afraid. The pool is 6.9 cubic metres with a surface area of approximately 10 square metres. An IBC is 1 cubic metre and 1 square metre surface.

Being black, the IBC could help heating the water a bit too.

Do any of you have any input in this?

[Keith Rowan]

if you're just using it for swimming, you won't really be producing ammonia in the pool to support plants unless, well.. you know!

anyways, i use an 8' kiddie pool to raise fish and i use 3 half IBC's as growbeds, and have approximately 150 fish in it

[Louise]

Well, I know it won't have that much nutrients. But still you need to filter pool water to keep it nice.

[David - WI]

Look for Intex Krystal Clear Saltwater System - it's absolutely fantastic; the water really is crystal clear, no algae, no red eyes after swimming all day, no scaly skin, no faded swimsuits.

Basically you "sanitize" at night (generate chlorine from saltwater) and then after the sun shines on the water for a little while the chlorine dissipates... you just don't swim while it's sanitizing.  We run the sanitizer 2 hours per night unless it's real hot and getting heavy use... then 3-4 hours but it shuts of automatically so it's no problem; just set it and forget it.

[Carey Ma]

Good idea!
I design and build natural swimming ponds as part of my business. I believe your IBC tote is more than adequate to act as a bio-filter. I would however, cut the tote in half and use the two halves as your filter. If you do not plan on eating the plants, you could plants some reeds and grasses to help uptake any nutrients (p) that “accidentally” get in you ool…hehe. I would also suggest using a small bale of barley grass on top of the media as a pre filter. I’m not on this site much these days but feel fee to send me an e-mail if you have any questions.
Break a leg & Cheers

[Carey Ma]

PS I didn't check where you live but beware of overheating your filters. you don't want to cook your microbe colony. Then you'll have a big stinkin mess.

[Louise]

Thanks Carey! The split tank makes sense!

 Please explain the deal with the barley grass. You mean as in dry straw, right? Would it not add nutrients in the long run, as it decomposes?

I live in southern Sweden, so a cool temperate climate.

Carey Ma said:

PS I didn't check where you live but beware of overheating your filters. you don't want to cook your microbe colony. Then you'll have a big stinkin mess.

[Keith Rowan]

barley straw "might" be beneficial to controlling algae..
but..
http://ohioline.osu.edu/a-fact/0012.html

[Carey Ma]

Right Keith very good link; but since this is not for AP and purely for swimming/ cooling, we don't need to worry about being cautious for the sake of the fish...There aren't any. We just want the water to be a bit clearer. The plants will gladly uptake any nutrients.

* Correction: Barley straw, not barley grass.