[JohnB]

In an attempt to help control my ever-increasing nitrate level, I created a little hydroponic pothos garden. Pictures and a brief explanation of the construction are available here.

Still too early to know if it's going to have any effect.

Let me know what you think.

John

 

[wedrnkbeer]

Looks awesome! Let us know how it works.

 

[Bruno]

i just put the plants in my tetra tec filter 9hang on back), vines took insite my sponges and all that

Looks great!

 

[tzembower]

Great idea, I've got to know if this helps!

Todd

 

[verrice]

Really interesting idea, and you did a great job putting it together. Looks great.

 

[JohnB]

Thanks for the comments. Just an update on what I thought was a very simple, straightforward design. It stopped working.

It worked fine when I tested it (repeatedly) -- water was pumped in the hole in one end and drained out the other. But after I turned the pumps off for cleaning the other day, the water no longer drains out the hole but instead overflows the top. Nothing blocking the tubing or elbow. The only thing I could think of is that an air bubble is trapped in the output elbow, preventing water from flowing through it. If I jiggle it around or shove something in the hole I can eventually get water flowing out. But I can't trust it if the power goes out.

One thing I tried is drilling a small hole in the top of the output elbow and inserted a 2-inch-long piece of airline tubing. I figured that would let trapped air escape and the tubing would prevent water coming out the hole. Didn't work, still no flow. Thinking the hole was too small with the tubing inserted I pulled it out and after some gurgling noises the water started flowing. Only problem is that without the tubing, water trickles out the hole.

So now I am completely stumped and open to suggestions.

John

 

[verrice]

Perhaps replace the elbow with a T so that your venting is equal to the size of your drain? You could then place a cap on that which allows as much air through as possible, but won't let things fall in or water to splash out.

Just and idea, but I'm no plumbing expert.

 

[JohnB]

That's a great idea, but I'm not sure such a T exists. The closest thing I can find is this:

It doesn't look like it has a flange to rest against the surface on the outside. It looks like it would just pull through the hole. Compare it to this:

John

 

[verrice]

I do see a small lip on it... perhaps a nylon washer would fit the bill? You could 'glue' one in place if that won't work.

 

[Nil]

Two ideas.

1) Brute force. Make the output significantly bigger than the input. Either a bigger output tube or convert the output to some type of overflow. If you do a bigger output tube, you should make it so that the highest point of the output is right where the output tube meets the end cap (so that the air has a place to flow out of and let the water take its place).

OR

2) Following verrice's line of thinking, use a PVC T to connect to the endpipe, and then find an adapter from the PVC to your vinyl tubing (drip watering system connectors might work).

Hope that helps. Love to hear how you end up fixing it.

 

[tzembower]

1) Brute force. Make the output significantly bigger than the input.

Bingo,

Do this and your flow will be fine.

Todd

 

[verrice]

1) Brute force. Make the output significantly bigger than the input.

Bingo,

Do this and your flow will be fine.

Todd

I certainly agree with the output being larger than the input, but wouldn't making it significantly larger really increase the noise level?

 

[JohnB]

I decided to try replacing the elbow with a T, since that involves the least amount of changes (and work). I should have the part in the next day or two. Interesting that when I ordered this $0.87 part the shipping was over $7 , and there is a $5 minimum order. We could always use more plastic buckets, so I added a couple of those to the order and the shipping price came down to $4.50. I really wish I could buy this stuff locally.

 

[mpmitche]

Let us know if this fixes it. I would love to try some kind of hydroponic setup (kinda a nerd) someday and this little baby looks great.

 

[Michael Menzer]

Has John B or anyone else had any measurable success with plants to lower nitrates? I've had little success with plants in my Malawi tanks and have often considered this.

 

[verrice]

Has John B or anyone else had any measurable success with plants to lower nitrates? I've had little success with plants in my Malawi tanks and have often considered this.

From what I've been told by knowledgable sources, is that your plants don't really remove alot of nitrates without a good CO2 supply. Normally that's in reference to underwater plants. Since these plants are also in the air, where we produce CO2 naturally for them, perhaps it'd work out better.

FWIW

 

[iceblue]

Even if it doesn't make a significant difference in nitrates it still looks really cool. 8) A living garden surrounding your tank will always inhance everyones viewing pleasure.

 

[JohnB]

Problem solved. I changed the elbow to a Tee and it works. Updated pictures and info are here. Now let's see if it actually does anything for my nitrates or just looks nice.

One thing if I were to do this again, I would not only use a Tee but also make the output a larger diameter than the input (as Nil suggested). Even when the ouput is flowing, it can't keep up unless I reduce the powerhead's flow rate to pretty low. I wanted a low flow rate anyway, so that's not really a problem, just a puzzle. I don't really understand why this is - maybe somebody could explain the physics to me.

BTW, it turned out the Tee did have a flange just like the elbow (the picture on the website was wrong), so no need to add a washer.

Thanks for all the comments and helpful suggestions.

John

 

[Butti]

Even when the ouput is flowing, it can't keep up unless I reduce the powerhead's flow rate to pretty low.

The powerhead generates pressure enough for a good flow at the input. However, when the water has to flow through the output, it relays basically on atmospheric pressure, which is probably not as strong as the pressure your powerhead generates. Hence, you need a larger output to have the same amount of water flowing in and out OR a powerhead set to low flow.

Please keep us updated on those nitrate removal results.

 

[verrice]

Glad to hear the tee helped! Good luck with the nitrates, but as was said, either way, it's a cool idea.