Filtering fresh water with plants

[Young Frankenstein]

I was thinking of making a 10g tank to prefilter my fresh water, straight from the faucet. I will put in fresh water aquatic plants, and leave the water in there for 2 days before use. The chlorine will dissipate and any silica and nutrients that feed algae will be eaten up by the roots of the plants. Whats you comments please. This is the natural approach to filtering

 

[JetCat USA]

it's the natural approach to bacteria too.

 

[Young Frankenstein]

<a href=showthread.php?s=&postid=10764286#post10764286 target=_blank>Originally posted</a> by JetCat USA
it's the natural approach to bacteria too.

i would have to disagree with you because everytime you refill the new water with chlorine will kill every bacteria

 

[EdwardPPS]

Unfortunately this won’t work because aquatic plants need C, Ca, Mg, N, P, K, Mn, Fe, Zn, Cu, B, and Mo in relatively narrow levels in order to take nutrients and grow healthy. Additionally, unhappy plants leak nutrients back to the environment. An RO unit is a better solution.

 

[Young Frankenstein]

I am so convinced this will work i will just have to give this a try

 

[Young Frankenstein]

Edwards part of the plant in water and part of it in dirt ? If it sounds weird what i am thinking is those plants here in Florida that clime walls.

 

[sunfishh]

O agios this is the way alot of natural water ways stay clean. They have a marsh upstream that strips a good deal of the nutrients out of the water. I personally would go with floating plants because they can out compete any algae for CO2. Besides if it works you will have discovered the next wave of water treatment in our hobby.

One more thing I would not be too concerned with bacteria. Most bacteria that lives in freshwater can not survive in saltwater.

 

[Young Frankenstein]

Sunfish I appreciate your comments, I do allot of reading but I am an electrician, more familiar with ballasts and bulbs , I would appreciate if you stick with this thread and help me out since you teach biology. I believe with the wright combination of plants this can be achieved very easily, chlorine dissipates within a couple of days and most likely leaving fresh water in a 10gal tank for a week will achieve my goals can you suggest some plants that I can pickup from a LFS ?

 

[JetCat USA]

Water Lettuce or Hyacinth.

 

[graveyardworm]

Heck, sewage treatment plants do it. I think your gonna find an RO unit is much easier though. Also i dont believe your tap water is going to provide enough nutrients or amounts of the correct nutrients to sustain the plants, and the water isnt going to be nearly filtered enough. It'll be a fun experiment though.

 

[Red Firefish]

I'm also curious what type of results you see with this, and would like to hear your results. Please do keep posting about this.

But... I'm skeptical about its efficacy and usefulness. First, you almost certainly won't be able to acheive a perfect purity in the water, since plants utilize macro- and micronutrients in distinct ratios that you'll be hard pressed to match exactly. This is assuming you can provide enough light and CO2 for rapid photosynthesis. Second, you probably won't be able test for all the mineral content that may accumulate if you were to use this water for top off. I guess I'm thinking primarily of controlling silicate , which feeds brown algae specifically, although there are numerous other compounds in municipal water (ones that don't have an easy to use colormetric test kit like silicate does). Maybe TDS would be another good thing to monitor? That would give you a quantitative method of comparison to traditional RO/DI water.

I hope those things don't discourage you; please keep us informed. Good luck!

 

[Young Frankenstein]

Thanks for the comments red fish. The 10g will be outdoors where there's plenty of sunlight, to achieve healthy plants I will use them climbing plants, where 1/2 of the plants roots will be in water and the other 1/2 in a flower pot. The build is almost 100% and I will post picks.

 

[Young Frankenstein]

I am guessing it will take a couple of weeks for the roots to develop enough, at that point after the water sits there for a week I will send it out for testing.

 

[Plantbrain]

For the low levels of nutrients you seek, aquatic plants cannot do the job and will add more nutrients back into the system.

Also, Chlorine will burn the plants, unless you add a dechlorinator or activated carbon prefilter.

I'd highly suggest RO, for a 10 gallon supply, it's much easier, less labor(how much would you pay yourself per hour?), less cost over time.

The Everglades restoration plan uses several series of aquatic flora to filter the water to induce native revegetation.

The PO4 starts at 1-2ppm, then goes through swamp forest, emergents(.5-.8ppm PO4), then submersed(.2-.5ppm), and finally to periphyton(0.003 ?? -.200).

As you get smaller sized flora, the amounts to provide sustained growth also become smaller.

When trying to process 100MGD, bioprocesses make sense, but when dealing with the 10 gallon?

Nope.

When placing plants in "pots", this is plain aragonite etc? Not soil or sand etc?

A few plants will do okay in arag, but many will not.
You will not get the good purity goal you seek here.

I can tell you that without running a single test.
Aquatic plants leach a lot of stuff into the water.
This leaching increases as nutrient stress increases.
So the lower nutrient levels you go, the more it will occur.
Few plants are good for Si removal, then, namely grasses.

If you keep the PO4 under control, then diatoms, which are the only real issue for Si, are easy to keep in check.

Also, if you use a DBS, plants, macro algae etc, then they leach more into the water than you can remove via a Fw plant.

I'd ask for test result and see what is in the tap(from the tap supplier) before trying a bunch of work that is not going to get you much for the effort.

While fun etc, it does not meet the goal you suggest you want.

Regards,
Tom Barr