Backyard Aquaponics
A place to discuss aquaponics

The Nitrites are over 2ppm or 4 ppm, the colors are too close to tell apart.
so you're saying there's a way to test nitrites higher than that?

Yes, but I don't know how.
TCLynx talks about it in her Peeponics thread here.

I see, she doesn't specifically talk about how to though, i'll PM her.

Anybody have suggestions as to stocking density? with 250 gal FT 250 gal ST and currently 200 gal of biofilter.

I've laid out my plans according to TC Lynx's "2 kg per 100 liters of flood and drain media filled grow bed"

and I get 26.6 fish for my 200gal of GB

I'll buy 30 fish and have an auxiliary filtered fish tank as a backup.

Does that seem right?

I wouldn't go adding new fish (stressed from travel) into a system with anything more than a trace of nitrites personally. However, you are talking about tilapia which do tend to survive some terrible abuse. Salt the water (I would salt to 2-3 ppt for tilapia since they are quite happy with higher salt levels) Just make sure you use plain salt (not table salt or iodized salt) I generally get a bag of the cheapest solar pool or water softener salt. Here is a link to a post with some numbers for figuring out how much salt for the volume of water and for salting you need to figure out the total system volume of water. http://www.aquaponiclynx.com/salt-for-fish-health If you salt more than 1 ppt you will probably not be growing strawberries this season.

Now my other advice still stands about the stocking density, especially if you are getting larger fish to start with. 1 fish per cubic foot of gravel bed or 1 fish per 7.5 gallons of grow bed. Since they are tilapia, I would say 25-30 fish And your bigger worry is that with access to the bottom of that size fish tank, you are going to have thousands of fry this summer. Your hospital tank is going to quickly become the fry tank.

Hello Chris,

How is the drain on their barrels system? I'm starting in aquaponics and do not have much information about it.

Emilio,

The drain is a simple loop drain, it works well in a situation like this where bell siphon is not desirable. it's very reliable as long as the incoming waterflow is adequate.

However if i could do it again i would made my own grow beds with a bell siphon, there is simply more room to grow vs. the barrel system.