My mixed design - Comments Please

[Cengiz BAYAZIT]

Greetings to all,

I'm about to complete my greenhouse. Here's a drawing of my aquaponics design. 

Here's how I imagine it'll run.

1. Grafity flow from Fish Tanks to Clarifier to take out the big stuff (I'm imagining a little more dense population than usual),

2. Gravity flow from Clarifier to media beds ->  2000 L sump -> Rafts

3. Pump in last raft to pump up to the NFT,

4. Gravity flow of collected output of NFT into the Fish Tanks

Any comments and advice would be much appreciated. (i.e I have some doubt about the location of the sump tank, or whether or not I need it at all :)) ). 

Thanks in advance,

Cengiz

[Bob Segraves-Collis]

You basically asked two questions:  1.  do you need a clarifier, 2. Is the design right?   As for needing a clarifier, no you don't NEED it.  Many systems run perfectly well with out one.  In the Aquaponics source original design by Sylvia, B. she had worms in her grow bed and they took care of any solids from the fish tanks.  With a dense fish population compared to grow bed volume, you would do well to have one.  

As for the overall design, the flow logic:  FTs -> Clarifier -> Grow Beds -> NFT -> FTs is fine.  The issue is how you use gravity and where to put the pump.  As for the gravity, here is a rule I would suggest you consider:  The output of one step needs to be higher than the input to the next to get proper drainage.  If you were to pump from the bottom of the fish tank to the input of the clarifier, have the output of the clarifier above the input to the grow beds with output above the input to the channels and the output of the channels above the tank then your system will cycle just fine. 

[Bob Campbell]

Have you calculated the energy use?

[Cengiz BAYAZIT]

Hi Bob,

Thanks for the quick answer. The clarifier (UVI Swirl filter/ Conical clarifier) is the green one in front of the FTs. The sump (after the media beds, before the rafts) is the tank in question. I put it there to keep constant height in rafts as a buffer for the flood/drain in the media beds. But I'm not sure if it will provide the desired effect. 

[Cengiz BAYAZIT]

Hi Bob (Campbell),

I only have one Water Pump and one Air Pump in the system. The water pump is a bilge pump (12V x 6Amps) = 72Watts. It's connected to a solar charge unit and a battery that'll run it for 5 hours in case of electricity outages. The Air Pump is 110 Watts total.  We have plenty of sun in Turkey, thus no lighting... And for heating , I'm planning a simple rocket heater.

[Bob Campbell]

Your energy consumption sounds good. The sump after the media beds can't hurt, but I doubt it will even out the water flow by too much.  It might help clear the water before entering the rafts and keep your roots a little cleaner. 

You could always abandon the NFT if the water gets too hot or cold, but that and the propensity for NFT channels to clog are my only concerns. 

On thing to keep in mind;  use large pipes.  Nothing less than 2".  You can always close off a pipe with a valve, but you can't make more go through a small pipe.  After a while pipes tend to restrict water flow.

Your design is laid out very similar to my outdoor system.  My pump draws more power than I like, but I think it's works pretty good. 

I'm not saying you should do what I'm in the process of designing, but just for grins have a look at this.

Cengiz BAYAZIT said:

Hi Bob,

Thanks for the quick answer. The clarifier (UVI Swirl filter/ Conical clarifier) is the green one in front of the FTs. The sump (after the media beds, before the rafts) is the tank in question. I put it there to keep constant height in rafts as a buffer for the flood/drain in the media beds. But I'm not sure if it will provide the desired effect. 

[steve]

I really like your layout, clever. Does not sound like the pump you are talking about will circulate your fish tanks in 1 hour as recommended. Just something to consider especially with a heavy fish load.

[drumurphy]

You might consider where in the loop your water will be the cleanest, and try to introduce that water to the NFT section - over time the raft tanks will collect particulate debris, roots, hunks of coco fiber etc. and that is going to foul the NFT, which is the portion of your design most sensitive to mucking up. Also, it's nice to introduce duckweed into your rafts - fish food and algae cover for open spaces, and you don't want that flowing into the NFT.  Hopefully as your water comes out of your media beds, it will be nearly free and clear of particulates. 

Also I'd consider trying to send your fish tank water directly into your media beds - put worms in at least the first 2 or 3 beds, and let them go at the waste rather than filtering with a clarifier - with a clarifier you will be throwing away lots of good mineral value every time you clean it - possibly devote one bed (first) just to worms - that way you can turn it occasionally if needed - At least for us, loss of micro-nutrients are our biggest problem - We only have raft tanks now, and want to exchange the clarifier/filter system for media beds in the near future - 

With those mods, If you still have particulates at the exit point of your media beds, that is where I would consider a filter point - build a simple mineralizer tank (good sized) loaded full of shade cloth - it will filter any really little stuff that gets past the media, and then bacteria can munch away at it - it should rarely if ever need cleaning, and if it does (if it starts to have unpleasant odor) you just drain and back hose the cloth from the top down - .

Spend a lot of time thinking about your water flows - each entry point needs to be below the previous exit point, so you typically need to elevate your pump destination pretty high. The fish tank could act as a sump (lowest point), pump up to media beds, flow to the mineralizer, flow through the NFT, into the rafts, into the fish. A nice big loop. Only one pump, no timers, switches, valves etc .Using exit risers, you can't overflow - put a bypass riser in your media bed in the event your bell siphon/s fail (clog) for some reason. Use oversized pipe. 

Looks like a fairly large system - what's your goal??

AM

[Cengiz BAYAZIT]

Dear Drumurphy,

How many worms is enough? Is there a per volume worn count guideline? :)

I remember reading difficulties about isolating duckweed from the rest of the rafts. How do I solve that? (put duckweed in the last raft before the NFT?)

Oh , and I forgot. I'm planning on putting Pumice into the media beds. We have plenty of that here.

I'll connect the rafts together with 3" pipes. I'm guessing they'll be OK because they're all interconnected at the same height, and will act as one big bed.

What's a bypass riser? Do you know where I can find more information on how to make one? It definately looks like something I need.

drumurphy said:

You might consider where in the loop your water will be the cleanest, and try to introduce that water to the NFT section - over time the raft tanks will collect particulate debris, roots, hunks of coco fiber etc. and that is going to foul the NFT, which is the portion of your design most sensitive to mucking up. Also, it's nice to introduce duckweed into your rafts - fish food and algae cover for open spaces, and you don't want that flowing into the NFT.  Hopefully as your water comes out of your media beds, it will be nearly free and clear of particulates. 

Also I'd consider trying to send your fish tank water directly into your media beds - put worms in at least the first 2 or 3 beds, and let them go at the waste rather than filtering with a clarifier - with a clarifier you will be throwing away lots of good mineral value every time you clean it - possibly devote one bed (first) just to worms - that way you can turn it occasionally if needed - At least for us, loss of micro-nutrients are our biggest problem - We only have raft tanks now, and want to exchange the clarifier/filter system for media beds in the near future - 

With those mods, If you still have particulates at the exit point of your media beds, that is where I would consider a filter point - build a simple mineralizer tank (good sized) loaded full of shade cloth - it will filter any really little stuff that gets past the media, and then bacteria can munch away at it - it should rarely if ever need cleaning, and if it does (if it starts to have unpleasant odor) you just drain and back hose the cloth from the top down - .

Spend a lot of time thinking about your water flows - each entry point needs to be below the previous exit point, so you typically need to elevate your pump destination pretty high. The fish tank could act as a sump (lowest point), pump up to media beds, flow to the mineralizer, flow through the NFT, into the rafts, into the fish. A nice big loop. Only one pump, no timers, switches, valves etc .Using exit risers, you can't overflow - put a bypass riser in your media bed in the event your bell siphon/s fail (clog) for some reason. Use oversized pipe. 

Looks like a fairly large system - what's your goal??

AM

[Cengiz BAYAZIT]

Oh , and My purpose;

It's not huge, the beds are 150cm x 75cm each. and the greenhouse is 75 square meters total.

This is a trial system . If I succeed , it will be a commercial venture , roughly 10.000 square meters.

I'm guessing sales won't be an issue with 12 million people in the city :)  

Cengiz BAYAZIT said:

Dear Drumurphy,

How many worms is enough? Is there a per volume worn count guideline?

I remember reading difficulties about isolating duckweed from the rest of the rafts. How do I solve that? (put duckweed in the last raft before the NFT?)

Oh , and I forgot. I'm planning on putting Pumice into the media beds. We have plenty of that here.

I'll connect the rafts together with 3" pipes. I'm guessing they'll be OK because they're all interconnected at the same height, and will act as one big bed.

What's a bypass riser? Do you know where I can find more information on how to make one? It definately looks like something I need.

drumurphy said:

You might consider where in the loop your water will be the cleanest, and try to introduce that water to the NFT section - over time the raft tanks will collect particulate debris, roots, hunks of coco fiber etc. and that is going to foul the NFT, which is the portion of your design most sensitive to mucking up. Also, it's nice to introduce duckweed into your rafts - fish food and algae cover for open spaces, and you don't want that flowing into the NFT.  Hopefully as your water comes out of your media beds, it will be nearly free and clear of particulates. 

Also I'd consider trying to send your fish tank water directly into your media beds - put worms in at least the first 2 or 3 beds, and let them go at the waste rather than filtering with a clarifier - with a clarifier you will be throwing away lots of good mineral value every time you clean it - possibly devote one bed (first) just to worms - that way you can turn it occasionally if needed - At least for us, loss of micro-nutrients are our biggest problem - We only have raft tanks now, and want to exchange the clarifier/filter system for media beds in the near future - 

With those mods, If you still have particulates at the exit point of your media beds, that is where I would consider a filter point - build a simple mineralizer tank (good sized) loaded full of shade cloth - it will filter any really little stuff that gets past the media, and then bacteria can munch away at it - it should rarely if ever need cleaning, and if it does (if it starts to have unpleasant odor) you just drain and back hose the cloth from the top down - .

Spend a lot of time thinking about your water flows - each entry point needs to be below the previous exit point, so you typically need to elevate your pump destination pretty high. The fish tank could act as a sump (lowest point), pump up to media beds, flow to the mineralizer, flow through the NFT, into the rafts, into the fish. A nice big loop. Only one pump, no timers, switches, valves etc .Using exit risers, you can't overflow - put a bypass riser in your media bed in the event your bell siphon/s fail (clog) for some reason. Use oversized pipe. 

Looks like a fairly large system - what's your goal??

AM

[drumurphy]

The point would be to put the NFT before the raft beds - the duckweed would be downstream from the NFT, and would need to somehow migrate through the media bed/mineralizer sub system to get to the NFT - love duckweed - free fish food  - 

Flows would be as follows -

1) Fish tank (lowest point) pump to media beds (highest point)

2) Media beds gravity flow down to mineralizer tank

3a) Mineralizer tank gravity flows to NFT  

!!!!  at this point I realize you are probably going to need more flow through the entire system than the NFT subsystem will need - so you would probably be diverting a portion of the flow from the mineralizer to the NFT, and the remainder to the raft beds; the NFT will flow to the raft beds as well.!!!

 

3b) Mineralizer tank gravity flows to Raft beds

4) NFT gravity flow to Raft Beds

5) Raft Beds gravity flow back to the fish tank

This exercise makes my other point - spend a lot of time visualizing the flows of water before you lock down your design - think about flows backing up, paces where flows will pool and possibly stagnate, how you will limit the build-up of debris, how will you maintain standard water levels in the various sub-systems, what oxygen levels might look like at various points in the system (important to maintain an aerobic environment almost everywhere, especially the media beds) - it's half the fun IMHO - your system will look it's best (well, cleanest) the day you fill it with nice clear water, and it will quickly fill up with life and gunk in ways and places you may not exactly appreciate ;) Once you know where and how much water you need throughout the system, then try to design your pipe as elegantly and simply as possible - i find that simplicity always works best - also, the less pipe and the fewer bends etc, the higher the flow rates, and the slower the gunk up rate ..... the more you can turn over your water the better everything is ...... anyway, think it all through, and then think it through again - tearing out pipe or rebuilding platforms because you need 5 more inches of elevation somewhere is a real buzz-kill .... been there ;). 

I assume you are using bell siphons to drain the media beds - The overflow riser I mentioned would be a simple secondary riser with an input slightly higher than the bell siphon initiation level, but lower than the top of the bed - if the siphon failed to open, water would flow down the overflow riser into the mineralizer rather than overflowing the bed and out on to the ground, which would eventually drain the entire system .... unhappy fish, recycle the entire monster etc .... a bad aquaponics day ..... this idea of an overflow may be (is probably) unnecessary as the big problem with bell siphons is the things not closing, rather than not starting, but I don't like any point that could possibly become a plugged up tank with no way to drain the water to where it belongs - it requires a 2nd bulkhead for each siphon point, and piping to the mineralizer - think of it as a taller bell siphon without the cap and exterior sleeve - again maybe not necessary as long as you do cleaning and maintenance on the siphons - I put the backups in our previous system - 

AM

Cengiz BAYAZIT said:

Dear Drumurphy,

How many worms is enough? Is there a per volume worn count guideline?

I remember reading difficulties about isolating duckweed from the rest of the rafts. How do I solve that? (put duckweed in the last raft before the NFT?)

Oh , and I forgot. I'm planning on putting Pumice into the media beds. We have plenty of that here.

I'll connect the rafts together with 3" pipes. I'm guessing they'll be OK because they're all interconnected at the same height, and will act as one big bed.

What's a bypass riser? Do you know where I can find more information on how to make one? It definately looks like something I need.

drumurphy said:

You might consider where in the loop your water will be the cleanest, and try to introduce that water to the NFT section - over time the raft tanks will collect particulate debris, roots, hunks of coco fiber etc. and that is going to foul the NFT, which is the portion of your design most sensitive to mucking up. Also, it's nice to introduce duckweed into your rafts - fish food and algae cover for open spaces, and you don't want that flowing into the NFT.  Hopefully as your water comes out of your media beds, it will be nearly free and clear of particulates. 

Also I'd consider trying to send your fish tank water directly into your media beds - put worms in at least the first 2 or 3 beds, and let them go at the waste rather than filtering with a clarifier - with a clarifier you will be throwing away lots of good mineral value every time you clean it - possibly devote one bed (first) just to worms - that way you can turn it occasionally if needed - At least for us, loss of micro-nutrients are our biggest problem - We only have raft tanks now, and want to exchange the clarifier/filter system for media beds in the near future - 

With those mods, If you still have particulates at the exit point of your media beds, that is where I would consider a filter point - build a simple mineralizer tank (good sized) loaded full of shade cloth - it will filter any really little stuff that gets past the media, and then bacteria can munch away at it - it should rarely if ever need cleaning, and if it does (if it starts to have unpleasant odor) you just drain and back hose the cloth from the top down - .

Spend a lot of time thinking about your water flows - each entry point needs to be below the previous exit point, so you typically need to elevate your pump destination pretty high. The fish tank could act as a sump (lowest point), pump up to media beds, flow to the mineralizer, flow through the NFT, into the rafts, into the fish. A nice big loop. Only one pump, no timers, switches, valves etc .Using exit risers, you can't overflow - put a bypass riser in your media bed in the event your bell siphon/s fail (clog) for some reason. Use oversized pipe. 

Looks like a fairly large system - what's your goal??

AM