Rapid PH shift and Bacteria

[Bronx19]

Hey guys, I was wondering if large PH shifts can cause any damage to the nitrifying bacteria?

[pitchblack]

No, at least I dont think so????

[Bruno]

Yes it will.

[Fishpimpin73]

From what I understand............

Yes it can.

But it would have to be a very MAJOR shift.
We are talking in the 10+ point area to have any real effect.
And if you have a shift that severe..........
Well, lets just say that losing some bac is going to be the least of your worries.

[goldenpigeon]

it can. the easyiest way to lose bacterial is to put the ph below about 5.5. then it will die

[Trebs]

The higher the ph the more bacteria will be needed to deal with a set bio-load. The reverse is also true, the lower the ph is less bacteria will be needed to deal with the same set bio-load.

So any lowering of ph will lead to the gradual loss of some bacteria (due to less food being available to the bacteria). Any rise in ph will mean a shortfall in bacteria and it will take time to catch up. How much the ph rises will dictate how long it will take to catch up and how much excess ammo and nitrite there will be during this period.

The bigger the change in ph is more pronounced the effects.

And as Goldenpidgeon said, really acidic conditions will lead to a major bacteria loss.

[Bronx19]

Thanks for all the info.

Im struggling to cycle my tank at the moment.

I have tried twice, and on both occasions the cycle stops after nitrites near zero.

Ammonia almost nears zero, but then begins to rise as nitrites fall.

I had a PH shift from 7.2 to about 6.5 over a few days, and I was curious if this may have caused a problem.

[lesley]

In my experience, a shift like that would not stop the tank cycling.

When I start a new tank off, I always get some filter material from one of my already existing tanks. When I initially started off I bought in some grotty water in which the filter material from the supplier of the fish had been squeezed into and was up and running straight away - put the fish straight in. I have never had a problem doing it this way.

The only time I had a problem was when I tried to start a tank off using one of the cycling products, almost killed all my discus. Never again, now I just put in used filter material and put the fish straight in.

HTH, Lesley

[Bronx19]

Thanks Lesley.

I have another question.

Do using products like 'Prime', which remove everything including nitrites and ammonia interfere with an already established tank, or can the bacteria still use the ammonia?

Also, if we are keeping discus and replacing 100% of the tank water per week, would the ammonia ever get to a point that harmed the fish?

[jim from sydney]

you should never change 100% in one go (if that is what you meant) it is fine to change all your water in one week but do it in stages say 4 times 25% or so . i do mine 430 liter tank with 15% every day it works fine for me.....that way you'll have no problems....Jim

[Bronx19]

Yep, by 100% per week I meant changes every odd day.

[Merrilyn]

Bronx, you aren't doing water changes while you are trying to cycle the tank, are you?

If you're doing a fishless cycle, it will prolong the cycle by months. If you are using hardy fish to cycle the tank, partial water changes are necessary to prevent the ammonia and nitrites from building up to lethal levels, but it does take a lot longer.

[Bronx19]

Nope, not a single water change on both occasions.

It all goes according to the book until the nitrites spike, and then fall.

Once that happens, the ammonia rises again.

I'm still adding half the initial ammonia each say incase its for some reason spiking again, I'll wait a 3-4 days and see if it falls.

[lesley]

Hi Jim,

I have not used Prime, so cannot comment. But if you were using something that was removing the ammonia, then how would the tank cycle?

If you put fish in when the tank is not cycled, then ammonia can build to lethal limits within hours. Likewise the nitrites if you are that little bit further along.

I think that cycling a tank this way would take some weeks. That is why I have used filter material from an already existing tank because you get up and running straight away. You do need to check your levels to make sure that it is working of course, but it has never failed for me. I don't put too many fish in initially.

HTH, Lesley

[ozarowana]

Your pH shift could be due to having quite soft water. The nitrification process lowers pH.

Your ammonia reading after the filter cycling could be due to the fact that most of the initial ammonia converting bacteria have died off and therefore cannot process the ammonia you are adding fast enough.


I'm still adding half the initial ammonia each say incase its for some reason spiking again

I initially add ammonia so you get a 5ppm reading, then after the nitrites disapper, keep adding ammonia (ammonia I was using was 37%) but only at two drops per day to keep it going. I think you may be adding too much.

[Merrilyn]

Bronx, review this thread on fishless cycling, and see if there is anything you may have missed.

Hope it helps:

http://www.discusforums.com/forum/viewtopic.php?t=895