Backyard Aquaponics
A place to discuss aquaponics

Help!

Had a fish death today (14 cm Koi), thought the 41 degree day may have something to do with it, but then tested the water (which I haven't done for 2 months (bad I know) and found a ph of 9 and Ammonia level of 0.5

A quick check on one of the threads tells me this is definately not healthy for the fish. What is the best (and safest) way to quickly lower the ph?

So far I have turned my waterfall on to constant running to improve DO and of course stopped feeding the fish (luckily I didn't getting around to feeding them yesterday or today anyway).

With 20,000 litres and no real water source to do a water change (other than the tanks which I think gave me the high ph when I topped up the pond), how do I best correct this problem - I have seen talk of Hydrochloric Acid?

It seems to be about the only unknown in AP world from what I've discovered but I am in NO way an expert. Just going on the advise I've recieved so far. It would take you quite a bit of HCL to bring your 20000lts down.
Plus having fish makes it harder because you cant just dump a large measure and see what it does as a large PH drop can be too stressfull to the fish. It seems that if your water source is of a high PH you start off up the creek without a paddle.
I suppose using a measured amount of HCL to try and bring it down at no more than .2 at a time is the only safe way. I have no idea how much HCL you would need to even make a dint in 20000lts of water though. I do know that 5ml knocks my 5-600 lts down by .2PH once a day.
Good luck hate to see fish losses even if they are only Koi.

BB, Koi are a beautiful looking fish and I remember my uncle paying a few hundred for a beautiful specimen 10 years back when he was still around. Not sure what they taste like but they do look good!

Just look like small carp to me. No offense Mike. I'm just kidding, I have 11 goldies in my system/s and they are tough buggers I'll give em that. Nothing wrong with useless... I mean ornamental fish to get the ball rolling. I do love your pond though I just need to buy my own property to do a similar size pond and stock some murry cod. Or just dig up the GF's block while she is at work. hhmmmmm.

250ml should move your pH about 0.2 points in 10000L...

I'm curious as to how you would go about adding 250ml of HCL to a pond that contains fish. If its added in concentrate to on end of the pond wont there be a dangerous amount in one spot and if the fish swim through it could it damage them?? Maybe add it into the waterfall, and/or a sump if you have one, Mike and, I know this is probably impossible but try and confine your fish to the other end until the HCL has had time to dispurse??? I don't know if this is a concern or not, Rup do you think? I'm just trying to prevent any more damage to your fish Mike.
That HCL is nasty stuff! The fumes burn ya nose hairs right off, I cant imagine what it would do to fishes gills!

looking at the size of the pond, you could add a cap full here and there and particularly in the waterfall. That should disperse the HCL well enough.

I think the real question is why is your pH so freakin high?

The fish should bring it down, so what is bringing it up?

I would test the tank water for pH and if the water source has a high pH then you need to get a new water supply.

Pre-mix it in a 10-20L bucket... then pour into water return.. and/or above air stone(s)... up your aeration temporarily if you can...

It will dilute and spread rapidly and shouldn't affect the fish...

You could also probably set up a drip with a plastic bottle and some drip irrigation fittings that would gradually add the acid to the flowing water over a matter of hours.

My pool water tends to rise and we always need to add acid. Probably the total alkalinity is too high and I should add some HCl, but I haven't bothered. If you have a lot of water spotting with your bore water you may have high TA as well. This site has a calculator for acid to lower TA, but it is for swimming pools, not for AP, so be careful. http://www.havuz.org/pool_pool/pool_mai ... linity.htm

Mike, this guy got the same issue?
viewtopic.php?f=18&t=6024&p=218006#p218006
Maybe compare notes.

But from what I have read, I think the fish pooing should make the system tend toward acidity - so if it is not, then what could be causing it. I know you are using expanded clay - so that can't be it. Not using lime stone or anything like that for the water fall!

Maybe you could salt it a little? Someone was saying you can get salt from B for less than $8 for 25Kg. Not sure how Koi go with a little salt.

Justin

Would seasol be raising the Ph?

No...

Good to know.
Rupe, if the system is cycled, then the pH "should" naturally drop?
Or is that a faulty assumption? Do some systems just run high?

As the system matures... pH should move as part of the "nitrification" process...

But if the system is buffered by source water supply, or growbed material... it may well run high for a long time....