Ray's New System

[RayS]

Finally I think I have loged in. I have been looking at these forums for about a month during this time I have put together a small system comprising of the Kids goldfish a buildge pump timer bath tub and the innerds of a washing machine the plants are spinich and lettice the growing medium course sand from the creek I have been adding yabbies and other bugs to the bath when I get all up to speed on the consept I hope to build a bigger set up. Mean while I have my shair of ? HELP 1;what is the ideal depth of growing bed ? 2;how often should you flood the beds? 3;how long do you flood them for? 4; How much flow? should the bed over flow? 5;once the bacteria hase developed what is the process of transfering it to another grow bed? 6;what is the ideal ratio of pond size to grow bed size? 7; What is the ideal fish stocking ratio? 8;Where do I buy good fingerlings? 9; What is a realy good fish for me good eating fast growing suited to the lovely climate here winter temps only fall to 0c rairley and summer rairley 40c this year rairley ubove30c 10; fish food? what type keeping tin mind I have acess to bulk grain cow fatting pellets what about left overs from ethanol plant will the yeast etc affect there helth?

[Murray]

Hi Ray,
Welcome and good to see another person starting on an Aquaponics journey.

It is good to start with a small system.
1 Ideal depth of a grow bed is 300mm. This is the generally accepted wisdom. Depth is needed to support the good bacteria colonies. The depth also provides a more stable environment. You will find some discussions on this subject if you search the forum.
2 There is no set time but most folk who run successful systems have a cycle time of about 45 minutes. It can be shorter or longer, but 45 minutes appears to work really well.
3 As for 2
4 In my system each grow bed takes about 180 ltrs of water to fill. I employ a 15,000 lph pump, so it fills 4 grow beds in about 4 to 5 minutes. It then takes about 40 minutes for the water to drain back to the collection sump and then into the fish tank. Then the cycle starts all over again.
5 No, the bed should not overflow. Ideally the bed will fill to within 25mm of the top surface of the gravel.
5 Once the system has cycled....the good bacteria has established....just hook up your next grow bed to the system and the bacteria that is already in the water will find it's way into the newly added grow bed. It may take a week or two until the bacteria colony expands to take up the new added capacity, but this will depend also on the amount of fish waste available to feed the bacteria.
6 1:1 is a good ratio by volume. This ratio is manageable and workable. It is possible with close management to go to 1 fish tank to 2 grow bed by volume.

I have to go now,I have an appointment. Perhaps someone else may answer the last questions.
Most of what you ask are pretty standard questions at the beginning, and you wil find discussions on these matters throughout the forum. You will enjoy the reading I am sure.

[RayS]

well it seems to me the courser the gravel the faster it drains the finer the growing medium the less often you have to flood it therefor less power usage? ****the growing of duck weed to feed fish? shorley this takes newtriants that could be better used to produce vegies?*******if growing duckweed would it hot be best to grow in a tank that receaved the water at the end of a cycle therefor using the last of the remaining newtriants?******rather than having one large fish tank why not have several such as fish tank to grow bed auto sifon fishtank over flow to ggow bed autosifen to duck weed grow tank float switch pump to top tank witch could be large enough to handle several cycles for back up a float valve installed at a low level in top tank supplied by another water supply eg tap or dam if dam stock with fish this suppl would be controlled by a battery operated timer as used in gardening systems of course no water would flow unless the water level in header tank fell below float valve if it was to supply water in the event of power failur ther would be excess water in the system which would over flow the botem tank possibly to grass etc. using this a large pump could be efficently used and run less often water oxigenated incorperating a vortex in line to top tank diferant fish sizes could be in differant tanks therefor differant feading programs *********am i thinking rite or not got this consept corect yet???????another t hought why not run water from pump to alot of polly pipe to solar heat it as the water temp must be the same as thaditonal ground temp ?? also it would seam a waist to flood grow bed at night as there issint much photo sinthisis happening again saving on power inputs????

[GaryD]

Hi,


****the growing of duck weed to feed fish? shorley this takes newtriants that could be better used to produce vegies?Of course, growing duckweed takes nutrients. Aside from the fact that we want to grow fish food, we want to remove the nutrients, too. Our duckweed tank is another form of bio-filter.


*******if growing duckweed would it hot be best to grow in a tank that receaved the water at the end of a cycle therefor using the last of the remaining newtriants?It can be done that way. It's a matter of what outcome you're seeking.


......also it would seam a waist to flood grow bed at night as there issint much photo sinthisis happening again saving on power inputs????Flooding a grow bed through the night ensures that the water continues to be oxygenated and it ensures that the substrate.....in which the nitrifying bacteria live......remains moist.

GaryD

[nick]

also with the flooding at night, plants actually do most of there root growth during the night, also there is no photosynthesis but plants are constanly absorbing nutrients and fish are pretty constantly putting it out so night time cycling is advised and should be considered mandatory when you have a large number in the tank.

Imagine if you have just fed your fish and turned the pumps off to the growbeds with only an air bubler going for the 10 hours of darkness your ammonia levels would be quite high by morning, and then in the morning you would feed again and again the ammonia output levels of the fish peak and you are still trying to play catchup from the night before.

Nick

[Murray]

In winter I turn my beds off at night, but that is only to try and preserve the heat in the fish tank/s
But generally speaking, it is best to keep the pumps going 24 hours a day.

[Martin A1]

We have had a cold snap (cold air/nights) couple of days in Sydney area and I have noticed a very quick 5 degree drop in my water temperature. I cycle at night and I am sure this has reduced my water temperature very rapidly.

My fingerlings are clearly feeling the cold and have not attacked their meals with the usual gusto.

[Murray]

I expressed my opinion in an earlier post, (long range weather forecaster hat on)
I would not be surprised if we experience an early and cold winter.

[fishfood]

I feed night and morning and turn my pumps off at night [ at the moment running 70 silvers and 50 trout] ammo always 00

[RayS]

so feed fish in morning then turn pumps on grow duck weed in last tank any other comments on my ramblings multi tank / finer mediums / back up idea /flooding system / heating system??

[Murray]

Grow mediums finer than about 10mm tend to block up after a while. I feel it is better to have the grow medium between 10 and 20mm in size. I use 20mm drainage gravel and it works for me.
When I first started in aquaponics I set up a grow bed using very course sand, but it started to block after about 5 weeks operation.

Back up, I use a fail relay switch which switches on 12 volt pumps when the mains power goes down for whatever reason.

Heating system, now that is my current worry as winter approaches. I am hoping to get an old solar system off my roof and convert it to run during winter and heat a holding tank of water that will act as a heat exchanger for my tanks etc. Last winter we had a very cold snap here and I heated my tanks using a couple of 1800watt immersion heaters. The power bill was shocking.

[GaryD]

Hi Ray,


.....any other comments on my ramblings....multi tank.....

I advocate the use of several smaller tanks rather than one very large one because you can, with careful design, operate a polyculture in the same water column without having the different organisms having direct contact with each other. You can also keep fish of different ages/species. From a risk management point of view.....if you have a serious problem with one tank, that's a drama but if you lose your entire set up....that's a tragedy.

GaryD

[fishfood]

I curently run2 1000 litre ibc/s and 1 750 litre tank all with different fish at different stages of growth [ i am going to add 2 more 1000 tanks ]all using the same water

[Murray]

FF, how do you have them joined up ? Are the tanks running in series with only one pump moving the water out to the grow beds ?

[fishfood]

Hi murray the first 2 ibc/s have a tee to the main pump .The 750 litre is on the return line with a 30 watt pump one of the new 1000 litre will be on the return from that [ its easy when your land has a slope] and the other 1000 still working on that one things for shore i mite take a while to think about it but i will only do it once