Help to start up of system

[tneilsen]

Hi

Well I have started to build what I hope will be a system that supplies me with both veg and fish. My current set is two 210 lt tanks under two 80 litre grow beds with a bell siphon (flood and drain) system. I am now pondering on what what to do next to commence the system. I have been running the system for a week now with no plants nor fish. I have been reading threads etc on start up and I am wondering what to do next.

I have the following questions I hope others will answer. SORRY if the ?'s seem stuipd but I want to do it right with minimal lose.
I have read that using seasol and planting some plants without introduction of fish etc will allow system to cycle. How much seasol does one use. Is it as per instruction as if one was fertilising plants and how does it affect the waterand introduction of fish etc?
I am receiving for free approx 50 young red claw over the coming weekend and was wondering if it is ok to put them in the tanks? If not what time frames.
I am currently using a 3000 lt per hour pump which results in the grow bed flooding and draining every 3-4 minutes. Is this Good/ Bad.

SIMPLE QUESTIONS BUT IMPORTANT FOR ME TO KNOW
REGARDS

[GaryD]

Hi tneilsen,

I have read that using seasol and planting some plants without introduction of fish etc will allow system to cycle.

Using Seasol does little to bring about cycling (cycling requires an ammonia source) but it will sustain plants while they are waiting for fish to be introduced into the system.

If you want to cycle a system quickly and decisively......find a source of ammonia. I've used urea successfully and others have use sulphate of ammonia (both available from your local garden store).

Some people use aged urine (humonia) but personally, I prefer to keep my food and waste elimination systems well separated. Pure ammonia is best - but can be hard to find. The key with fishless cycling is to add the ammonia source very gradually.......while undertaking water tests daily.

Here's how you go about fishless cycling:

Add your ammonia source and wait for the Ammonia figures to reach around 2 - 4ppm. Continue to test each day and you will see the nitrite levels start to rise. Once they reach 2 - 4ppm, you can ease back on the ammonia source and they will suddenly drop to zero......and your system will be cycling.

You will need to continue adding a bit of ammonia (or something that generates it) to maintain the rate of colonisation of Nitrosomonas and Nitrobacter bacteria after cycling commences......until you're ready to put your fish into the system.

You can use fish to cycle the system but it takes much longer and, if you get it wrong, the fish end up dead. Once again, daily water tests are important.

Personally, I'd wait until you settle the system down before I introduced the Redclaw but that will depend on whether you have somewhere else to put them. If you have to put them into your tanks, you will have to go with the more extended cycling arrangement. The tendency is to overfeed crustaceans (my partner has eliminated two lots of Redclaw by ensuring that they were "well fed") so feed very small amounts until things get going properly - probably weeks in this weather.

Gary

[tneilsen]

Thankyou. I have not placed claws in tank instead I have used cheap feeder fish so if all goes south I will not be losing much. (Not that the fish are not important). I have planted two grow beds with lettuce and added seasol to water waited for a couple of days and finally added the fish. Was not sure of amount of fish per tank . System currently set up with two 210 litre tanks and two 80 litre grow beds and now approx 12 fish. How much fish is too much? I was under the impression from what I read that it is approx 40-50 fish per 1000 litres. I was ultimately looking at stock Jade Perch to eat. I also purchased 2nd hand 1000 litre tank in whic I am currently trying to ready for use in the near future. I was under the belief that there is a specific ratio of tank volume to grow volume. Is this correct? Thanks again

[GaryD]

Hi tneilsen,

I have planted two grow beds with lettuce and added seasol to water waited for a couple of days and finally added the fish. Was not sure of amount of fish per tank . System currently set up with two 210 litre tanks and two 80 litre grow beds and now approx 12 fish. How much fish is too much?

Your system will not have cycled......and it will now take weeks given that you have elected to cycle using fish.

Now that you've got them, I'd leave it at 12 and see how they get on in the coming weeks. The system will eventually cycle and you can supplement the nutrients provided by the fish with a bit of Seasol.

Your two little grow beds will probably be too small as your system matures and your fish grow. Consider adding a trickling bio-filter to your system. It will bolster your nitrification and aeration.

If you can also provide some basic mechanical filtration, that will also enhance the efficiency of your bio-filtration.

I was under the impression from what I read that it is approx 40-50 fish per 1000 litres. I was ultimately looking at stock Jade Perch to eat.

There is no simple answer to the question because it depends on feeding rates, feed protein levels, fish species, water temperature, etc.

Ultimately, the carrying capacity of any system is determined by its ability to process waste and your capacity to maintain dissolved oxygen at the level appropriate to the species that you are keeping.

While they are small 40 - 50 fish may not be sufficient but, by the time they are 500g each, they may be too much. Attempts to systematise stocking density are usually the stuff of nonsense.

I was under the belief that there is a specific ratio of tank volume to grow volume. Is this correct?

Without qualification, the notion of component ratios is another popular mythconception. You need enough bio-filtration to deal with the number of fish that you elect to keep (taking account of the feed rate). If you don't include mechanical filtration in your design, you will need much more bio-filtration .....and your system will still be limited in terms of it productivity and resilience.

Gary

[tneilsen]

Hi Gary thanks for the information. Was wondering what you mean" Consider adding a trickling bio-filter to your system. It will bolster your nitrification and aeration."
Regards

[GaryD]

Hi,

Given that you only have very small grow beds in your system, I was suggesting that you connect a trickling filter into your water column. It will, at little cost, enhance your nitrification and aeration.

Let me know if you require further guidance or pictures around this.

Gary

[tneilsen]

Hi Gary
YES I would like some further guidance and pictures in relation to trickling filter into your water column. At this point in time I have made what I think are some OK modifications to filter grow beds firstly I have placed a pond filter into 80mm PVC sleeve this is connected to the inlet hose in grow bed. Furthermore I have attached a container containing bio balls and a layer of green house cloth on each grow bed water outlet which goes back into each of the two water tanks. I have also installed a fish tank filter into the tank with the fish.

I do have a ? which would be appreciated if you could give some guidance.
In relation to the water inlets into both beds. The hose from the tank which houses the pump goes up the t junction to back of each bed with the above mentioned sponge filter attached to each of the two hoses. Given it is a flood and drain system is it ok to allow water to flow into each grow bed from one outlet or is it better to place further hose across each bed so that the water enters each grow bed via a trickle effect.

[GaryD]

Hi,

Here's some photos of simple trickling bio-filters.

Photo 1 - a pair of simple trickling bio-filters made from plastic barrels. The water from the fish tank (via mechanical filtration) enters the bio-filters at the top. We use inexpensive plastic bowls (with holes drilled in the bottom) as water distributors......to ensure that the water enters the filters in a shower pattern.....to avoid it channelling down through the media. The water percolates down through the media and drains through the bulkhead fittings at the bottom of the barrels.

Photo 2 - we use oyster shells as media for the filter. They get them free from an oyster processor and they offer a workable surface area for the bio-film (and subsequently the bacteria) and a good void space which avoids clogging and provides for excellent aeration.

Photo 3 - in this photo, we're using a trickle filter to supplement our old Baby Q filtration module which (at the time of the photo) hadn't become fully conditioned. This demonstrates how easily a trickling bio-filter can be connected into a system to boost nitrification and aeration.

Given it is a flood and drain system is it ok to allow water to flow into each grow bed from one outlet or is it better to place further hose across each bed so that the water enters each grow bed via a trickle effect.

The reason for using a watering grid is (so the story goes) to ensure that the solids are evenly distributed throughout the grow beds.

Since (in my humble opinion) you are not supposed to be putting solids into your grow beds, you don't need a watering grid......period! Having said that, I believe that they are still a feature of BYAP kits. While they are useless, they do look good.

My strong advice to you is to skip the watering grid and stick with your bits of filter foam. They will serve you much better in the medium to long term.

Gary

[tneilsen]

Thanks Gary
Was wondering about the first pic. Does the water come from the main fish tank to the bio filtering tanks (on top) then back to main tank prior to being pumped to the grow beds? I am assuming that the flow of water from tanks to bio filter tanks on top is continuous?. How can one increase the current two 80 litre grow beds to a third bed without compromising the overall total water drop of two fish tanks being 210 litre each. I am aware about using a sump system but this will require another pump and floats which I have read are not reliable over extended period of time as they require adjusting periodically. Given this I want the most simplest system that is effective. Furthermore, I have refrained from placing the fish in both water tanks due to the build of crap from the fish so the fish remain in one tank with the fish filter and the second interconnected tank remains free of fish but does house the pump to take water to grow beds. I am really enjoying aquaponics and will continue to expand current small set up. Currently I am in the process of gathering further materials to expand. Have scored a 1000 litre tank have also purchased a further three 210 litre tanks need to grow beds. With this in mind how many grow beds would one require. Not sure how to set up would you have any ideas?

[GaryD]

Hi,

Does the water come from the main fish tank to the bio filtering tanks (on top) then back to main tank prior to being pumped to the grow beds? I am assuming that the flow of water from tanks to bio filter tanks on top is continuous?

Yes, you can discharge the water that drains from the bio-filters into grow beds where it then drains from the grow bed back into the fish tank. You can also divide the flow from your pump and put some of it into your grow beds and the rest through your trickle filter.

How can one increase the current two 80 litre grow beds to a third bed without compromising the overall total water drop of two fish tanks being 210 litre each. I am aware about using a sump system but this will require another pump and floats which I have read are not reliable over extended period of time as they require adjusting periodically.

You don't need to set the grow beds up as flood and drain. You can set them up for continuous flow which will help you to avoid the fluctuating fish tank levels.......and, despite what some people will claim, plant growth will be unaffected by the change.

If you set your system up as a CHOP(constant height one pump) you will not need a second pump and if you go down the continuous flow track, you won't need any timers, float switchers or auto-syphons either.

Given this I want the most simplest system that is effective. Furthermore, I have refrained from placing the fish in both water tanks due to the build of crap from the fish so the fish remain in one tank with the fish filter and the second interconnected tank remains free of fish but does house the pump to take water to grow beds.

You could connect both tanks together and place the fish in one tank and the pump in the other.

The water would flow from the fish tank (via a centre pickup pipe) into your first grow bed (via a solids trap of some kind) and then into your second grow bed. It would then drain back into the second tank (which contains the pump). The water would get pumped up to the bio-filter before percolating down through the media and back into the fish tank.

The benefit of doing it this way is that the water entering your fish tank is clean and well-aerated. Let me know if you have trouble following this and I'll point you to a diagram that illustrates what I'm talking about.

Have scored a 1000 litre tank have also purchased a further three 210 litre tanks need to grow beds. With this in mind how many grow beds would one require. Not sure how to set up would you have any ideas?

The number of grow beds that your system will support is dependent upon the volume of nutrients that your fish (and the beneficial bacteria) produce......and the plants you grow (and other things). A 1,000 litre tank would be capable of supporting at least 10 such 200 litre grow beds.

Gary