Backyard Aquaponics
A place to discuss aquaponics

Thanks for the info guys.

Ok i'll mess with the flood and drain time.

I can't do 15 minutes on because the gravel GB is huge and takes about 15 minutes to fill.

Ok so what I'll probably do it go with something like 30 minutes on 30 minutes off and see if this helps.

Mantis, we haven't had much success with constant flow. SOme plants did really well and some didn't so I think F&D is a compromise for all plants.

Thanks all!

You could do 15 on 45 off if you get a bigger pump

zman, we've considered it however we have 2 roadblocks.

1. no more money. we have 800GPH pumps,.
2. we'd have to upgrade all our plumbing.

Is that 800GPH at 1 meter head? I have a 1050GPH pump that goes down to a 800GPH at 1 meter height for like $40. Also you shouldnt need to change the plumbing apart for an adapter for the new pump.

we have no money left for this project at this point. I know there are are some pretty inexpensive pumps but we already spent more money than we were given. ack....

Its not the inlet pipes, the 1.5 inch drains are pretty maxed out right now. I know I know, why didn't we use 2" piping... Cost was the factor. 2" fittings costs substantially more and also we were given a whole pile of free 1.5 fittings.

I'm with Rupe that the "off" time is too long. 1 hour off in the heat of the day could burn a lot of plants, especially sensitive ones like eggplant. Some of those plants in the pics looked like the leaves were drooping, an indication of drought conditions. Other than that probably just typical new system syndrome; PH, iron, and low on other nutes.

yeah, I'm hoping its the typical new AP syndrome.

Changed the off time today. Its now running 30 on 30 off.

Hi all, so far not much change. Strawberries are growing really well and everything else just seems to struggle. We've got a second batch of plants and we'll see how things go.

One thing that occurred to me. If plants in gravel bed are dying because of hot gravel, why are the plants also dying in the raft beds? It seems systemic. Maybe just new AP sydrome. Damn that patience.

This advice is probably worth what you paid for it....
The plants appear to be dying from nitrate/(nitrogen) deficiency. Yellow leaves and purple stems give a clue.

Also the DWC lettuce mortalities point in that direction.

This leads me to wonder how many fish you have, how much you feed daily and how long the system cycled?

A quick fix may be to add some kind of nitrogen source (fertilizer). I don't think it would hurt to try. I wouldn't change more then one thing at a time, but thats just me.

thanks jd, yeah we have increased feeding and added more fish. The system has been cycling for about 3 months. We seeded the system with mature water from another system.

Doing some research and talking to some people here is one conclusion that might be relevant and also good info for us all to know.

Most of us know the importance to pH and nutrient uptake. It seems that when pH isn't in the optimal range you can compensate for it by having high nitrate levels. So if you pH is 8 of below 5 your plants could still thrive as long as nitrate levels are high. Some research going on at the local college show this. A large system that was studied had no pH remediation at all (pH was below 5!!) but because nitrates were 200(+) it compensated for the low pH. Not only are there really high concentrations of nutrients, but they are at the roots all the time. Very different that traditional farming.

Ok nuff for now...

Hydroponic operations always used to run between pH 6.2-6.8.... but many are now run at pH 5.7-6.2....

It's more to do with trace element uptake than nitrate levels... which probably show elevated levels in the studies because the plants and nitrification are performing to max...

All my systems, and many other members.... run at pH 6.0... sometimes lower...

ahhhhhh! Plants still are struggling. All seedlings are slowly dying. Starters that were transplanted in are also slowly dying. This is KILLING me, I'm slowly losing the kids excitement!!

Ok so heres what we're doing:
Pump is on 30 minutes off 45
maxicrop is still being added a tablespoon a week
We stopped iron for a bit.

Nitrates still are low (10-30 ppm) so the only thing I can think of at this point is there's not enough nitrogen for the plants. Increasing feeding and going to add fish this week.



Last question: what is a no fail, super tough plant we can grow under challenging conditions?

I like to plant grass seed in my new beds, it stabilizes the gravel and shades it too.

Basil?? Don't worry about rates being low, a reading simply means all the nitrogen isn't being taken up by the plants. A reading if 0 and pale leaves would indicate a n deficiency

haha basil seedlings are even dying. Ack...