Backyard Aquaponics
A place to discuss aquaponics

This might be the same as asking how long is a piece of string, but is there a rough time frame for the PH to drop once a system is cycling? My system has been running with fish since the beginning of the month and my PH is still at 8. 1 fish died but I think that was due to a nitrite spike. By the way the fish had ink blots across its nose is that normal for tilapia?
I know patience is a virtue, but I've got lettuce and strawberries on the go and I really want to impress my friends, I mean will high PH cause lettuce to bolt or is it just the heat that does that?
The system is working here's the proof

It's different for every system and for some systems the pH never drops. The good news is that most of these systems work anyway. Just watch for deficiencies like iron (which is a common one). Chelated iron helps and using Seasol or Maxicrop in a foliar feed is usually good. Don't get carried away with using either of these, just spray when you see signs indicating that there is a problem.

Thanks Scotty, is PH a contributing factor to lettuce bolting? because all those in the picture are incredibly bitter.

Is it correct that the high system ph will still prevent the plants taking up iron, even when you add chelated iron?

Mine ran for about 3 months with goldfish etc and never dropped. Stayed above 8 the entire time.


Once i put 10 trout in and then started feeding 3 times a day. Also added some iron and seaweed feeds it finally dropped to about mid 7.


If its up above 8 just keep an eye out on the iron, iron gets locked out at about ph8 and above.

The leaves will be yellowy with green veins.

Hi Anthony, sorry I missed this post, with so many threads on BYAP's Forum, it's hard to keep up.

I'm not sure about the pH but try taking the lettuce and washing it, then put it in the fridge for a 2 or 3 days and see if the bitterness is gone. This usually works for me and I've had some lettuce that was super bitter when it came from the garden.



I suppose at some point this would be true but the pH would have to be really high and I'm not sure what the cutoff would be. At one point I was adding Maxicrop plus iron in a system at pH 8.2 and it seemed to help.

It's not perfect, but foliar feeding is a good way to get nutrients to the plants if you think they are being locked out by the pH of your system water.

Cheers

This chart helps you understand what is available at certain levels of PH. Iron lockout begins at high 7's. The important thing to remember is the only way to get iron into your system is to add it yourself. It isnt available in the feed itself.

Hey charlie, got a bigger version of that chart at all?

(wish we could have higher than 800x600, even as an attachment)

Download the IBC of Aquaponics (link at top of page), it is in there, along with a heap of other useful info!