Backyard Aquaponics
A place to discuss aquaponics

My systems is about 5 months old: viewtopic.php?f=18&t=21526

Water temp is 77 - 79 F.
Nitrites < .5 ppm
Nitrates > 160 ppm
Ammonia < .5 ppm
pH 8.0 - 8.2

Added 50 tilapia about a week ago.

Prior to adding fish, the plants were not doing that well. Snap peas grew well at first, now wilting.

Swiss Chard growing very slowly.

See attached pictures.

What can I do? Is it the pH (I've been told not to chase pH)? Why do I not have the lush growth seen in other aquaponics systems?

are the windows on a south wall?
any supplemental lighting? what kind of fish feed have you been/are you using?
how far below the gravel does the water come up? i found that i had problems until i dropped the water level to a couple inches below the surface.. it doesn't look like any specific nutrient deficiencies to me, but i'd probably treat with a couple capfuls of maxicrop with iron before doing anything else (besides making sure i was using a good fish food)
oh,, and get some red wiggler worms in those growbeds

Definitely don't chase the pH by adding acid directly into the main system. I would treat any top-up water with Hydrochloric acid (Muriatic) to a pH of 6.0 (and maintain it there) the day before adding it into your main system... the how and why has been covered on the forum many, many times, so you should be able to search up recent thread that covers it.

Keith
Thanks for your reply.
Yes, windows are facing south. Do you think I still need supplemental lighting? Was avoiding due to expense.

I am using tilapia feed - powder - from premium fish food - recommended by white brook tilapia farm where we got our fish.

Water comes up to about 1.5" from top. Was considering raising the level, but maybe not!!

Have been neglecting the addition of worms...will get that done right away.

Mr. Damage
Thanks for your advice. I hadn't added anything due to the fish, but your procedure will allow me to finally address the pH problem without fear of hurting the fish.
Thanks!