Backyard Aquaponics
A place to discuss aquaponics

Sounds like a good idea. Welcome to the forum Steve.

And some sea shells in the system will decay when the PH is naturally too low, and the stuff that breaks off and enters the system will raise the PH naturally.

That's what I do.

Of course, I live 1/2 block from the ocean.

take care,

jeff c

p..s. nice system

Great looking system!

Do the tomatoes get any natural light?

Thanks Jeff!
I was a 10 minute drive from the beach when we lived in Corpus Christi, but now it's more like 21 hours
The pH has now climbed back up to 7.4 right now and NO3's are down to around 30, so that's really no big deal anymore (water exchanges do wonders for concentrations). I will however keep the sea shells in mind for the v2.0 system I have in the works. I know my wife has a "TON" of 'em around here somewhere.

Thanks Chuck,
There's only a very short time when the sun shines through the window and that's in the AM, maybe about 30-45 minutes. Other than that, the only light they see is artificial, and from T12's at that (just plain ole shop light with "daylight" bulbs in them). I may need to end up moving the small system over to the campus as a "demonstration system" and wanted to keep the costs as low as possible right now. Without a grant, money for operating a system would likely be just slightly more than nonexistent. Figured a demonstration system would be a great motivator for our department dean's support.
Time will tell!!

Just a note about the shells, make sure to put them in a bag or stocking or something so you can pull them out easily if the pH goes too high. Shells make a great natural buffer that will only bring the pH up to 7.6 but that is still too high for most plants to be really really happy. I know this from experience (don't use shells as media.)

Looks like U are hooked and U are having lots of fun!
U also understand the nitrogen cycle... So U will be OK.
Some time people add some crushed oyster shells in the system, which helps maintain continuous/stable KH in the system.
Law KH can result in PH crush , which can kill all your fish.
Bio activity naturally reduces the KH since the bacteria uses Ca.
Good luck!

By the way a swirl filter, if I think I understand U is called a vortex, and it is a mechanical prefilter meant to remove solids, with a drain in the bottom. Yes it works with centrifugal forces.
Water comes at an angle at a lower part of the container, which is conically shaped at its lowest part, and exits at a higher point.
Some time additional entrapping elements are put inside to help remove the sediment (brushes, netting..)