Backyard Aquaponics
A place to discuss aquaponics

i'm just getting started but i might need some help. i'm not sure i've got everything setup correctly. here is my system:

indoor system, water temp stays close to 70 degrees F [21 C], air temp varies from 65 to 80 degrees F [18 to 27 C]. 250 gallon [1000 litters] FT that drains into a 40 gallon [150 litters] settling tank which is pumped into a 90 gallon GB [340 litters]. the GB is flooded and drained slowly 4 times a day, i have coco ~1cm^3 cubes mixed with shredded coco and a thin base of lava rocks. i started cycling with a few gallons of pond water and i've been cycling my system for 6 weeks. i have 20 small goldfish; 2-3 inches [5-7.5 cm] and a couple dozen seedlings. i started off around a Ph of 7 and slowly added some HCl to drop down to about 6.5

however, i'm not seeing much plant growth and i've had several seedlings die. also i'm showing zero ammonia, nitrates and nitrites.

so i can only think of two possibilities:

1] i got zero bacteria from the pond water but FT too big for those little goldfish and that is why i'm showing nothing?

2] system is working perfectly and i just need to get some bigger fish?

What are you feeding the fish?

Is there any algae?

picture would help - see here viewtopic.php?f=4&t=21754

In a very young system you might find that the settling tank is not required.
Best outcome will be if fish waste goes direct to the grow bed.
so switch your system from FT to GB to sump/settling tank (pump to FT).

you have enough fish but they are probably still a bit small and the system a bit new.
But as goldfish grow quickly (should be larger in 6 months) that number will be heaps.

you need to move the fish to a pellet diet with around 30% protein and veg material
(go for an omnivore pellet not a high protein pellet)

in mean time you can *carefully* boost your plant load using a liquid seaweed fertilizer with *small* amounts of Nitrogen (N) and low Phosphorous (P). Watering can directly onto grow bed but not more than once a week.
It will also give you some trace elements and Potassium (k). And help with the bacteria.

You must monitor Ammonia and Nitrates if you do this and stop immediately if they lift.
Probably find that present bacteria simply copes with the small load being produced by the fish.
Being indoor your issue may be light.

As you get more Nitrogen in system over time from fish you need to go to a low N and low P seaweed extract.

you pH is fine - don't add HCL to it.
Anything less than 7.8 just leave it as-is and don't play around with it.
You don't really want to be at 6.5 at this stage as you will have acidic issues later.

omega one flakes http://www.omegasea.net/products/nutrit ... ter-flakes

no algae

see the previous post, but the food is at 41% protein

i initially added some sea grow 16 16 16 a few times but i've been trying to go with out to see if the plants will survive off the fish alone https://smile.amazon.com/dp/B00UBY2PEY/ ... UTF8&psc=1

i put up a Mylar sheet to maximize the light from the small south window and i have a small grow light to help out, GB on top, FT to the right and settling tank to the left

here is a zoomed out picture, ignore the keg-orator to the bottom right

Feeding fish typical aquarium flakes won't cut it. Need a complete diet. See the post above from elf Perth. Plants need nutrients to grow. A complete feed will have the necessary nuts needed for the most part. Plant can't grow from nothing. Change feed.

any recommendations for fish food? for both gold fish now and maybe trout in the future. preferably via amazon.

thanks for everyone's help

don't get too caught up about that, especially with goldfish. it is miles cheaper to supplement than it is to buy lots of fish food. And even then you will have to add stuff. So going with a good all round organic liquid fertiliser should not be seen as a negative - you only use a small amount and your plants will appreciate it.