Alroc

[Merv]

Murray,

This is my first time to post a message. My system only has Goldfish at present but am getting Silver Perch tomorrow. The grow beds have some vegies in them. They all seem to be copying with my beginnings but I have lost some fish. I have attached a image of the set up. I will post some more details later.

I use Alroc on my land here at Werombi. Have done so for a couple of years. Great product. Difficult to get down here but well worth the effort.

Could you tell me which alroc product you supplies with the Aquaponic Kit?

I am having trouble with the water Alkilinity (170ppm) which is making my ph (8 +) stay quite high. My beds contain granite but must have some limestone in it. Alkilinity was over 200 but am using Sphagnum Moss in the water to reduce. It is a bit of a battle to get the right water quality.

Could you advise on some method the help with the high Alkilinity?

Regards,
Merv Lawrence

[Murray]

Hi Merv, I am very happy to see that you have your system hooked up and running.
On the pH thing, perhaps you need to go to an aquarium shop and get some pH Down to help you out until the system cycles (the good bacteria establishes) properly.
It would appear that your system has not cycled as yet and the good bacteria has not yet properly established itself.
It is always a bit difficult to control pH while the system is at this point.

You will find that the pH will normalise once the system has cycled.

"Several acids (carbonic, nitric and nitrous) will be produced as a by-product of the nitrification process. This has the effect of driving the pH down. " The Urban Aquaponics Manual by Gary Donaldson. P54


It is a bit of a job while waiting for the system to cycle and very regular testing is required.
When using the pH Down, go easy.....small adjustments is the way to go. It will take several days to get it down.

I found that once my system had cycled I have not needed to adjust the pH since then. Aquaponics is just amazing....once everything is in balance it just rocks along.


Some others may like to comment on how they managed their pH in the early stages.

Muzza

[billo]

It may be a good idea to check out the food safe nature of Ph up and down. I am pretty sure that in food fish circles those products can jot be used to alter ph if the fish are to be used for food... something to consider anyway.

[Murray]

Good point Billo, I have heard that some people use lemon juice. I don't know how many lemons you may need to use or how well it works as I have not tried it myself.

·To lower pH, use sulphuric acid. Avoid dramatic changes - use small amounts to gently ease the pH down. The Urban Aquaponics Manual . Gary Donaldson P54.

I hope this helps

Muzza

[GaryD]

Hi,

I don't know what the health implications are of using pH Down but it does contain phosphoric acid which will promote the growth of algae in your system.

You can use lemon juice to lower pH.....it's what I used.

Gary

[nick]

if you want to adjust the pH of the system try a trip to your local hydroponics shop. They often sell food safe acids for altering pH of hydroponic systems which will be suitable for use in aquaponics.

Just change it slowly as it will affect fish negatively if done quickly, but it will also positively affect the ammonia and nitrite levels that are usually high during initial cycling. By that I mean that the lower the pH the happier fish will be with higher levels of ammonia and nitrite. also if you have limestone in your system it will serve to buffer the addition of acid so you will be relatively safe to add the acid. the pH is high at the moment but the limestone will not allow the pH to go too low, which is known to affect the uptake of minerals by plants.
CHeers Nick

[GaryD]

Hi,

If pH drops too low, nitrification will be inhibited. I'd suggest that you manage it in the range pH 7.0 to 7.5. Nick's correct......small changes will help to avoid stressing the fish through wide pH swings.

Gary