Sounds plausible for a drip system for my RAS?

[Cecil]

It's been suggested by a prof friend that I set up a drip system to continually add fresh water to my RAS system at a rate of 1 to 5 percent per day. (I'll still clean waste feed and solids from my clarifer periodically). This is due to size of the fish I have which require continuous feeding through out the day for optimum growth. I have a water line under pressure from my well water distribution network that is connected to a garden hose which terminates with a plastic spray nozzle. I usually use this to clean my clarifier filter material and add make up water to 55 gallon drums which I mix with salt.

Anyway I'm thinking I could mount the garden hose it to the fish tank and have it barely open to allow water to enter the tank. At the small rate of 1 to 5 percent per day of the system volume (3.25 gpd to 16.25 gpd) I'm not concerned that there will be any danger of temperature shock from the well water that is in the low 50's. I'm not thinking iron will be an issue either at that small a rate. Oyygen would be low and nitrogen high but if I direct it into the agitator boil it shouldn't be a problem at that small a rate?

As far as overflow a bulkhead on the fish tank itself is not an option. To wavy and crinkled to allow a good bulkhead fit and frankly I don't like the idea of drilling into the tank. So my other option is a bulkhead at the water line of the 55 gallon clarifier. Since the siphon automaticially keeps the tank and clarifer at the same level, I'm assuming that shouldn't be a problem. I'm thinking a dry run (actually wet one LOL) would be a good idea as in directing the nozzle into a 55 gallon drum to see what kind of of setting I need on the nozzle to get the flow I want.

Thoughts? Ideas? Better Ideas?

[arachdog]

Doesn't sound like a bad idea. I'm going to be doing something similar for my setup. I don't think you have to worry about lack of 02 or excessive N2 at those flow rates. If your concerned then run the intake water over your RBC. I'm actually going to be using scheme water for mine so I've got chlorine to worry about as well. But I don't think it'll be a big issue.

One thing I think might be a problem is maintaining a consistent flow rate. Since its going to be a very small orifice its going to be very prone to blockage with particulates and scale. So it'll probably need regular adjustment. I'm actually leaning more towards a solonoid valve and a timer for my system, mainly because I'm really lazy and I know I'll forget to adjust it on a regular basis.

[Cecil]

Thanks for the response spiderdog!

[bunya boy]

Hi Cecil and Arachdog,
Being a bit of a purist and having adopted Aquaponics because of it's operation principles, I tend to disagree with your proposal to continually add water to your systems.

One of the advantages of the AP system is that it uses about 10% of the amount of water for a soil based garden of similar size. By adding 1 to 5% water by volume each day, you are effectively negating this advantage. On your figures, it would take 2 days at 5% to blow away any water saving features the system presents, and that's not on here in Oz with increasing water restrictions.

Another advantage of the AP system is that it contains and supplies all nutrients required for plant growth, disposes of fish waste in the process and does not dispose of nutrient rich "waste" water into our streams, rivers or Lakes. These nutrients are environmentally undesirable and entirely preventable with a functioning AP system. What you are proposing is doing the opposite of the desired outcome in this respect. Your Clarifiers are not Biofilters for the growth of Bacteria etc and therefore do not remove any nutrients at all in the long run! Where does you backwash water go? Back into your supply water? I think not, but perhaps I'm wrong?

Where does the 1 to 5% of displaced "old" water go? Again, I warrant it doesn't get recirculated or re-used in you supply water! I guarantee it doesn't get fed back into your well supply!!

Sure, you are going to need some make up water to replace that which is lost to natural evaporation and transpiration, but not at 5% a day!! Anedotally, a 1000L system will need about 40 to 50L makeup over a month. Even at 1% per day with your proposal, that equates to about 300L ! or about 10 times as much as for a functioning system per month. At 5% a day = 1500L : 1.5 times you system capacity!!

As I said, a bit of an AP purist, but I wouldn't entertain such a waste of water and despoiling the environment with either nutrient rich Fish waste water or HP waste water being discharged into any waterway. Perhaps you are going to use it in your soil based gardens? I'd like to find out.

Cheers IanK :confused:

[arachdog]

Yeah your right BB water changes are somewhat against the ethos of aquaponics and if the system is designed to be in balance then they aren't strictly necessary. My proposed system is actually not aquaponics at all its pure aquaculture so water changes are in fact required. Although I have got half a plan to reduce them to a minimum by only changing water when the EC goes over a certain amount. I also intend to use the displaced water on my garden (if you could call it that..) so its not a complete waste. I believe the reason Cecil is considering them is because he intends to run a somewhat unbalanced system with more fish than can be supported with his growbeds.

[GaryD]

Hi Ian,


Anedotally, a 1000L system will need about 40 to 50L makeup over a month. Even at 1% per day with your proposal, that equates to about 300L ! or about 10 times as much as for a functioning system per month. At 5% a day = 1500L : 1.5 times you system capacity!!
How much water you go through in a recirculating aquaponics system will depend entirely on how many plants you grow.

An AP system that uses just 50 litres of water per month is a tiny system...... particularly when you consider that a heavy-bearing tomato plant in full fruit might use upwards of 10 litres per day on its own.

Remember, plants may be 80+% water (depending on the plant) so, if you're harvesting much, you're chewing through the water.

In reality, a backyard-scale aquaponics system would probably lose in excess of 50 litres a month in evaporation alone.

Gary

[Cecil]

Hi Cecil and Arachdog,
Being a bit of a purist and having adopted Aquaponics because of it's operation principles, I tend to disagree with your proposal to continually add water to your systems.

One of the advantages of the AP system is that it uses about 10% of the amount of water for a soil based garden of similar size. By adding 1 to 5% water by volume each day, you are effectively negating this advantage. On your figures, it would take 2 days at 5% to blow away any water saving features the system presents, and that's not on here in Oz with increasing water restrictions.

Another advantage of the AP system is that it contains and supplies all nutrients required for plant growth, disposes of fish waste in the process and does not dispose of nutrient rich "waste" water into our streams, rivers or Lakes. These nutrients are environmentally undesirable and entirely preventable with a functioning AP system. What you are proposing is doing the opposite of the desired outcome in this respect. Your Clarifiers are not Biofilters for the growth of Bacteria etc and therefore do not remove any nutrients at all in the long run! Where does you backwash water go? Back into your supply water? I think not, but perhaps I'm wrong?

Where does the 1 to 5% of displaced "old" water go? Again, I warrant it doesn't get recirculated or re-used in you supply water! I guarantee it doesn't get fed back into your well supply!!

Sure, you are going to need some make up water to replace that which is lost to natural evaporation and transpiration, but not at 5% a day!! Anedotally, a 1000L system will need about 40 to 50L makeup over a month. Even at 1% per day with your proposal, that equates to about 300L ! or about 10 times as much as for a functioning system per month. At 5% a day = 1500L : 1.5 times you system capacity!!

As I said, a bit of an AP purist, but I wouldn't entertain such a waste of water and despoiling the environment with either nutrient rich Fish waste water or HP waste water being discharged into any waterway. Perhaps you are going to use it in your soil based gardens? I'd like to find out.

Cheers IanK :confused:

Excellent points BB and I sure wouldn't knock being more environmentally friendly and cutting costs at the same time. Just like spyderdog though, so far my venture is purely aquacultural and I need something to buy me time until the darn nitrites drop back down to zero. I'm thinking the drip thing could just do that. The fish in the tank are quite valuable not only once they reach a large size, but they come from a source that has a name and is in demand. It looks like I can sell all I can produce to a middleman if I want to.

[Cecil]

March 25th I need to celebrate with a beer. Wait a minute I usually don't like beer. :o Anyway, since putting the bluegills in the system February 2nd nitrites have finally dropped to zero again! So the latest test is ammonia 0.0, nitrites 0.0, and nitrates are 40 or 80 mg/l but I can't be sure as the two colors on the chart look identical to me. It could be I'm an artist by trade and I've trained myself to be so color perceptive I get confused at times.

[arachdog]

Good news Cecil ! No need, for you to drink beer mate I'll have two to cover you.
So did you end up doing the drip system or did you just wait?

[GaryD]

Hi Cecil,



So the latest test is ammonia 0.0, nitrites 0.0, and nitrates are 40 or 80 mg/l but I can't be sure as the two colors on the chart look identical to me.

Your system has cycled. As for the confusion around nitrate levels.......don't worry either one is OK and will be more than enough to grow plants.

Gary

[Cecil]

Good news Cecil ! No need, for you to drink beer mate I'll have two to cover you.
So did you end up doing the drip system or did you just wait?


Hey is it true your beer bottles in the land down under at at least a liter?


No I didn't get to it. Couldn't afford the fittings believe it or not. The economy is so stressful here we're just hanging on.

[Cecil]

Hi Cecil,


Your system has cycled. As for the confusion around nitrate levels.......don't worry either one is OK and will be more than enough to grow plants.

Gary


Thanks Gary. Good news from a respected veteran like yourself!

[bunya boy]

[QUOTE=Cecil;20501]Hey is it true your beer bottles in the land down under at at least a liter?
[QUOTE]

Have a look at this if you don't believe Stubby sizes in Oz!
http://www.google.com.au/imgres?imgurl=http://www.ntnews.com.au/images/uploadedfiles/editorial/pictures/2008/05/14/3beer.jpg&imgrefurl=http://www.ntnews.com.au/article/2008/05/15/4121_news_pf.html&h=543&w=900&sz=62&tbnid=pA90H9-7cx19tM:&tbnh=88&tbnw=146&prev=/images%3Fq%3Ddarwin%2Bstubby&hl=en&usg=__2HU10ekENH7wCzSO6eLfpwezAMc=&ei=Vx-sS5TWC4qOkQWO1Ni0DQ&sa=X&oi=image_result&resnum=6&ct=image&ved=0CCQQ9QEwBQ

Cheers IanK

[Cecil]

[QUOTE=Cecil;20501]Hey is it true your beer bottles in the land down under at at least a liter?
[QUOTE]

Have a look at this if you don't believe Stubby sizes in Oz!
http://www.google.com.au/imgres?imgurl=http://www.ntnews.com.au/images/uploadedfiles/editorial/pictures/2008/05/14/3beer.jpg&imgrefurl=http://www.ntnews.com.au/article/2008/05/15/4121_news_pf.html&h=543&w=900&sz=62&tbnid=pA90H9-7cx19tM:&tbnh=88&tbnw=146&prev=/images%3Fq%3Ddarwin%2Bstubby&hl=en&usg=__2HU10ekENH7wCzSO6eLfpwezAMc=&ei=Vx-sS5TWC4qOkQWO1Ni0DQ&sa=X&oi=image_result&resnum=6&ct=image&ved=0CCQQ9QEwBQ

Cheers IanK

:eek::eek::eek::D

[arachdog]

Haha, no its not true cecil. Bb is doing what we call 'taking the piss'. It does exist but only in a small part of Australia.
375ml used to be the standard. Now a lot of beers are only 330ml(I think they are hoping we didn't notice). You can still get some domestic beer in 'king browns' though, which are 750ml.