an easier filter

[Eric]

I have two growbeds full of gravel and I want to put up nft tubes. I had them up and running before I got my own place. I live in Costa Rica, where getting AP stuff is like hunting snake feathers. So I use an ibc tank for my ft, and another cut into two gbs. When my tubes were up before, my plants in them did poorly because the roots got coated with bioslime and algae. They had no filter and so they didnt work. So my question is, can I fill a piece of pvc with gravel and use it to clean the water just before the tubes? Im think say two feet of tube with caps that have bulkhead fittings and some shade cloth or screen to keep the gravel in the tube. It seems like it should clean out solids and eliminate the slime on my roots. I use A a cheap strainer with a screen that has small holes to catch solids before they get in the gbs, then use them on my bonsai and other plants in dirt.That seems to catch a lot of solids. Would a tube with gravel work? I was thinking about mounting verticle and the water coming in the bottom then throught the rocks then out the top to the tubes. Or should it be one tube/filter for each grow tube? I would put them over the gbs so any leaks wouldnt lose water. What do y'all think? Seems like less work and cheaper, plus ot having to build a swirl filter or use a sump. Or maybe this idea is too simple and wont work. Opinions and constructive critisim would be great, thanks for your time!

[David]

RFF (radial flow filter). A few pieces of PVC, two uniseals, a bucket and a small barrel or trash can and you are pretty much there. Maybe add some bird netting or similar filter screen since you are doing NFT.

[George]

You could try flow from gravel beds to NFT.

[Eric]

I would do the nft after the gb's. But there very low, two feet high maybe. Im going to try bottle caps in a bucket as a biofilter. If it doesnt work a swirl filter is next. Thanks.

[Pieter Swanevelder]

Do you use a Sump Tank (ST) ? - or do you GB flow gravity feed back into your FT?