Backyard Aquaponics
A place to discuss aquaponics

Yep be careful i had fare bit of lime spread over 2 grow beds [1 cup full] and had heavy rain overnight and the ph went from 6 to 6.8
I had been adding small amounts and nothing was happening so i dug a hole in the back of a grow bed and was useing that to add lime when it flooded it used a bit each time

That sounds like a good way to buffer on first thought but then, I suppose it only works well under a roof.
However, if you did the same thing with shells, it might not bring pH up much but wouldn't risk a sudden rain shower boosting your pH beyond safety.

RIGHT... no dead fish this morning or now at luinch time... and they are throwing themselves at me as i walk past... even the silver perch are unusually flighty.. i will test it this afternoon and go from there.

cheers

test 1 yesterday ...
and test 2 today about 20 minutes ago....
PH still quite low hey, safest surest way to up it a little...
1000L tank, under a patio roof....

I still can't understand why everyone gets so hung up on bringing their ph up. Every system I have ever had sits at about 6 or lower and the productivity is fantastic.

I think recently I read somewhere that Dr Savidov had been finding he was running his systems at lower ph, or something along those lines.

Once a long time ago I tried to bring the ph of my 4 bed system up because I panicked, all literature said you had to keep your ph up. I quickly gave up on the idea and since then I've never added anything to any system to try and raise ph.

SWEET! Ph can stay where it is then cheers EB, less stress for me. system been running all day now and will run continuous until thursday night, then back to normal i think...

Well not so fast!!!! If a system cycles at a high pH, then the bacteria that colonized it were probably well suited to that pH range so when the pH fell, it crashed a bunch of your bacteria and the result is having to re-cycle the system a bit to recover. Bringing the pH back up will let the original bacteria recover while leaving the pH low you will have to wait for bacteria that are better suited to the lower pH to take over.

That is kind an oversimplified view but I think it kind explains the situation.

In places where the pH is low and everything gets cycled up that way and everything is fine that way then it is ok. But if you have an ammonia spike because the pH dropped, that is not so good. And in a system where you can't get the ammonia and nitrite to go away, that is not so good either. A trace is one thing but anything above .25 ppm is more than just a trace and operating with between .25 ppm and 1 ppm of ammonia or nitrite all the time just doesn't seem right to me.

There is another slight worry in my mind. If your test kit says the pH is 6, you don't actually know if it is just 6 or if it might be way lower since 6 is as low as the test kit goes. I think if one runs a system at the lower pH, they had better have a way to measure a range of pH lower than 6 since most fish are not going to remain healthy in water that gets down to a pH of 4-5.

I know EB has been managing at a low pH but his systems are not having ammonia spikes and his fish are not dieing of it.