Crayfish and Algae Aquaponics | Ask The Aquaponics God

Crayfish and Algae Aquaponics | Ask The Aquaponics God

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  1. The is always less output than input when it comes to eating and pooping. Yes there will be poop but it will be less than what was eaten. That being said, spot on, not a replacement for filtering.

  2. I would think that using bottom feeders to process fish castings to reduce the size of the waste products would decrease the processing time for the bacteria to decompose the solid waste in a media bed system.

  3. avoiding primitive algae, put a lot of secondary more evoluted algae, and a lot of plants, cause ressources are limited those plant will eat a lot of the potential food of others. the secret is the ratio : number of fish, surface of roots, cubic meters of water… and a UV light to prevent primitive algae reproduction. but algae is not a problem unless you want to have a bath in your pond cause it doesn't seems mentally to be very clean, in fact those algae are cleanning your exesses of nutrients and it is good for water that needs it. it will desapear in water that doesn't need it like every aventis ground plants that apears in soil that needs it. nature is perfectly designed, cause nature evolute in a system that was created by nature herself..

  4. Freshwater crayfish solve a huge problem.

    You still need mechanical filtration such as swirl filters and bio bubblers because when you mechanically increase the stocking density, you need to mechanically augment filtration methods.

    Crayfish are detritivores though, they don't just eat fish shit and then shit out crayfish shit; that's a close-minded and uneducated perspective. The problem with aquaponics systems isn't waste, because that's exactly what you want, that's exactly what the nitrogen-fixing bacteria live off of which run the system. They do perfectly fine with effluent and ammonia in solution (gill exhalation and urea) but they don't do great at breaking down solid wastes (poo) because it's just too large.

    Anyone who has done any reading or research into wastewater treatment, sewerage and septic systems, agricultural manure management, composting and gardening or just biology, in general, knows that poo is in fact very nutritious (for the right things) and the major problem with poo wastes (besides pathogen quarantine) is creating systems which mechanically break down solids at rapid rates and support the right bacteria colonies to bioconvert waste nutrients into usable nutrients.

    Crayfish and detritivores, in general, are a creature which does exactly this. Firstly, they don't just eat fish shit, they eat most wastes. If you feed your fish BSF larvae, mealworms, brine shrimp, baitfish, lettuce, scraps or anything in addition to fish pellets, crayfish will pretty much consume whatever the fish don't, including the pellets. This is perfect because scrap foods are high in nutrients and readily accessible by natural bioconverters (fish and detritivores) for conversion to useful resources such as ammonia. Seriously, the best thing you can do with uneaten food is either scoop it out so it doesn't clog the system, or feed it to something that will bioconvert it, like crayfish. They'll also eat dead fish as well as poo. However, crayfish don't just eat and shit, they also excrete ammonia, like fish, which is directly accessible and they mechanically break down poo to smaller pieces which make it more accessible to root bacteria and the bacteria within worms.

    Crayfish definitely do solve a problem, they're just not a sole solution, they're an addition. They are a complex natural aid to a robust mechanical filtration system which extends the life (between cleaning) of filtration modules by bioconverting waste (or unconsumed) nutrition from the fish into readily accessible waste (urea – ammonium) and more workable waste solids (smaller poo pieces and likely less in total). They're an invisible miracle. You can surely survive without them, you probably won't notice much benefit with them but they're just another little addition to aquaponics. You add a lot of these little benefits into a balanced and stable setup and you'll notice big improvements (like natures biome) but you won't really attribute it to any one part.

    The only thing to be really aware of with crayfish is that you can't go in with delusions of grandeur thinking you're going to run a super productive cray farm in the bottom few inches of your fish tank feeding you cray every few weeks (like I first envisioned when I started researching) but given a decent sized system and proper separation you could probably have 3 or 4 easily in the tank and have a healthy cray every 4-6 weeks, maybe 8, for dinner.

  5. I with my 12 yr old son rake crawfish from the ditches after a good rain with a leaf rake … we get maybe 20 to 30 mainly tiny ones up to medium size crawfish each time we rake.. we have local wild caught perch about 30 … and caught wild 5 catfish also about 30 gold fish largest about 6 inches. All this in a ibc tote with top cut off and used as grow bed. Last fall i noticed some thing in my discharge tank little gold fish fry 5 of them..WTHeck they got sucked up and dumped into the grow bed wiggled thru the drains and into discharge tank. Did not feed them nor do i feed the main tank for some reason about oct they quit taking the small floating pond pellets. They start back on warm days mid march thruout spring and summer. We have massive amounts earth worms we rake back the leaves we piled and boom …30 mins to an hour five gallon bucket 1/4way full straight worm no dirti feed few to chickens not too much feed to fish till the quit taking then drop some down for catfish and crawfish.. drop some in discharge tank for crawfish if there are any and put 300 or so into grow bed maybe more 1000…then rest into compost far as the crawfish go they are wild not expecting them to last some do some dont lots get eaten right away perch love them as do the goldfish and the goldfish love tadpoles…i did have one crawdad that lived on the suction pipe in main tank it would come around if i had food it would come take the offering…

    The whole system is outside exposed to the elements…my first year total disaster rains washed a acid from the oaks before i realized causing a massive perch die off but the goldfish survived.. restocked the perch from the creek . Kept going. Lots of alge…worms survived first winter not all maybe 1/2 this winter i think they are done…time to restock…
    I dont clean the tank bottom its got lots of leaf little no packed the catfish keep it worked along with crawfish. I just restock crawfish as long as can hoping for pregnant perch this year keeping an eye for more babygold fish…
    Oh and my system is a constant flow…pump cheap from lowes 750 gph with 0' head pressure. Mine is now bout 3-4ft so im getting about 225 to 300 gal per hour turn over rate…winter water is ok but spring is awesome crystal clear its clearing off i noticed yesterday…tomatoes and spinach first two years…going to try just strawberries this year…tomatoes in ground actually in composte bin in chicken pen that has been work over very well this past year plus loaded with 6monthz of rabbit manure from 5 rabbits and straw….

  6. The autozone front door trash can barrel makes me want to eat these veggies. And as far as the answer goes to this, snails and shrimp. Having too many is silly because this is aquaponics. And as Todd pointed out below, plecos are good too. But you want as little algae as possible.

  7. @Brooklyn – how about adding shrimp on a commercial size DWC system water beds, such as the system you suggested to the Norway guys. Shrimp is very profitable, so it would be a great addition to a commercial system. thoughts?

  8. Algae is fine in the fish tank IF you have an easy replaceable filter that keeps it from being sucked up into your system and all other parts of the system does not have water exposed to any light source. OTHERWISE, the algae will clog the pipes, or grab onto the roots and suffocate your plants. I've seen hair algae in my tank grab onto all my other water plants and overgrow them like a parasitical infection. Best to pull as much of that stuff out as soon as you can as it can really clog up filtration and pipes. Heck I've seen it strangle baby fish and feed of their carcasses. Pretty freaky. So I put ghost shrimp in my system to keep the algae down, but I let the stuff on the sides of my tank flourish as the fish love it and having a little phytoplankton in the water is good for my goldfish as they absorb algae through their gills.

    I'm going to add crayfish to my system as well. But remember that those are ambush predators and any fish you have in your system will become fair game. Plus you'll need to add about 1' wall above the water level all around the perimeter of your fish tank as those buggers climb and jump. Worst smell is a rotting crayfish corpse under your cabinet. Oh and they need a lot of caves and they WILL propagate which means you'll need a filter to keep their babies from being sucked out into your grow beds where they will start munching on the roots of your plants.

  9. Been following your chanel for the last few months and I'm glad this question was asked. I want to add crayfish to grow and eat maybe to sell. Honestly, I have yet to see anyone give an answer for a dedicated tank or growing system for Crayfish. Last question when if your book going to be back on Amazon Id like to buy it so that I can have more info about how you run systems.

  10. I use Plaqoes to control algae in my system. I use one in each tank and They do an amazing job at consuming the algae and mine don't need any special care or food or maintenance. My two small tanks are 275 gallons each and one plaqoe per tank does fine. Love the channel and please keep up the amazing work 👍

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Media Bed, Aquariums, Cycling, and Feeding | ATAG

Media Bed, Aquariums, Cycling, and Feeding | ATAG