Pwc and water cycle.

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skiweeangel

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I know the common thought of doing a PWC frequently should not slow down your BB build up, but I think I am experiencing just this right now.

Backstory: massive ich infestation killed off entire 55gal stock. Gerrrr. I have since added 5 giant danios, changed out 1/2 of the carbon in my marineland magnum 350 pro filter for fluval biomax, (charcoal was the only media in it from the start), and added a new to me fluval U3 filter to hopefully seed it for use in the future for a QT tank and cleaned the crap (literally and figuratively) out of my tank. I have been checking my water every two days and doing my normal 50% PWC every week.

I have not seen ANY ammonia or nitrates during my testing. I am using my API FW master test kit and u know it is working because my two other tanks give me proper readings. My sons 55 gal tank that I added 3 Congo tetras to showed a slight bit of ammonia for a few days and now is completely gone with a slightly higher nitrate concentration. This is how I know my kit is working properly.

Question: do you think do to the light bio load of only 5 danios the frequent and large PWC's could be stripping the ammonia from the tank too quickly to allow a greater amount of BB to build up and continue the cycle on to the other stages? Should I lessen the frequency and size of my PWC's or just add more fish and continue of from there?
 
So you are doing a fish in cycle? When doing a fish in cycle you do need to let a LITTLE bit of ammonia build up (not over 0.25ppm). If there is no ammonia your BB will have nothing to consume. So you don't want it over 0.25ppm but you don't want 0ppm either. This is why you do your test then do a PWC accordingly. Eg: do test. Results are .50ppm do a 50% PWC.

Because of the small amount of fish in a large amount of water the ammonia will take longer to build up.
 
If you decide to increase your stock, just do so very slowly so your bacteria have a chance to adjust to the increased bioload. Spread it out over a few weeks & only add 1 or 2 new fish at time (per wk) if possible. Then just keep an eye on your parameters & do pwcs as Mumma suggested (if amm/nitrites get to .25 or higher) and you should be fine!
 
Just hold off on your PWC (defiantly do one if needed. Ammonia/nitrite over 0.25ppm) but keep testing and see what your tank is doing. You shouldn't need to add any more fish to help your cycle. Then when it's complete, add some more fish slowly. No point in exposing any more to the cycle.
 
I was reluctant to add more fish and I was testing before PWC. I fishless cycles this tank first but then with the ich die off I am now trying to rebuild the BB. While I was doing my weekly PWC I and looking at my results I started thinking I was stalling out the rebuild of the cycle. So thanks. I will hold off on my PWC until I see some numbers again.
 
Just realized this was in the getting started section and not my usual getting started section! I bet this helped get some faster answers!
 
Well if you think about it, you will never have 0 ammonia while cycling, even when doing frequent water changes. Just because it doesn't register to an exact shade on the test doesn't mean anything, it's not like the test is exact, it goes .25, .5, etc. As long as there are fish in there ammonia is being created.

The bacteria colony is going to grow or shrink based on the amount of food supply it has, it doesn't need a certain level to start working.
 
jetajockey said:
Well if you think about it, you will never have 0 ammonia while cycling, even when doing frequent water changes. Just because it doesn't register to an exact shade on the test doesn't mean anything, it's not like the test is exact, it goes .25, .5, etc. As long as there are fish in there ammonia is being created.

The bacteria colony is going to grow or shrink based on the amount of food supply it has, it doesn't need a certain level to start working.

Yes, but what I was getting at is if there are few fish, large amounts of water and very frequent, large PWC there won't be much ammonia. Isn't it better to leave the levels as close to .25 as possible not zero.
 
Yes, but what I was getting at is if there are few fish, large amounts of water and very frequent, large PWC there won't be much ammonia. Isn't it better to leave the levels as close to .25 as possible not zero.

The .25 'rule' is just something people kind of advise by, it's not really anything scientific at all, it just happens to be the lowest measurable mark on the API ammonia test.

If you wanted to get technical, you could look at an ammonia toxicity chart and figure out what a safe level of ammonia is based on tank temp and pH and go that route.
 
jetajockey said:
The .25 'rule' is just something people kind of advise by, it's not really anything scientific at all, it just happens to be the lowest measurable mark on the API ammonia test.

If you wanted to get technical, you could look at an ammonia toxicity chart and figure out what a safe level of ammonia is based on tank temp and pH and go that route.

That 'rule' was the one I was going by because it is the most commonly known and accepted.
 
I'm a rulebreaker, what can i say. =]

I think the idea that everyone repeats all the time is when fish-in cycling to keep levels to .25 or lower at all times if possible, I don't think there is any benefit to maintaining it at .25 though, but that's just me, I've heard that it can go faster with a larger concentration of ammonia, but without someone having an intimate knowledge of the ph/ammonia relationship I wouldn't really advise keeping any measurable level at all.
 
jetajockey said:
I'm a rulebreaker, what can i say. =]

I think the idea that everyone repeats all the time is when fish-in cycling to keep levels to .25 or lower at all times if possible, I don't think there is any benefit to maintaining it at .25 though, but that's just me, I've heard that it can go faster with a larger concentration of ammonia, but without someone having an intimate knowledge of the ph/ammonia relationship I wouldn't really advise keeping any measurable level at all.

Fair enough. I've always thought that the more 'food' the BB have the better/faster they can multiply. More food = more BB.
 
Fair enough. I've always thought that the more 'food' the BB have the better/faster they can multiply. More food = more BB.

Both yes and no. There is a limit to the amount that will grow based on whatever is the limiting factor. Bacterial growth takes place in several stages; 1) Lag phase, where the bacteria are introduced to a new environment (broth, solid media, or our aquariums) 2) Log Phase where bacterial "growth" is exponential. Bacterial growth is based on the number of bacteria residing within the system, not the size of the bacterium. Because all three stages of life (Lag, growth, and death) are occurring within the system simultaneously this stage is when the number of bacteria dividing out strips the number dying. 3) Stationary phase, where growth=death (the phase we seek to maintain within our aquaria) 4) Decline or Death phase. Just what is sounds like. It is the opposite of the log phase but may not be exponential in number dying, depends on the limiting factor within the system.

Limiting factor: of all the things an organism (or colony) needs to survive the thing in the lowest available concentration is the limiting factor. No growth can happen with out the presents of this thing.

So, in a rambling-studying-for-microbiology-test way the answer yet again to more food= more BB, both yes and no.

Sometimes I am not thinking about the task at hand because my mind seems to wander. But I have had time to think about this post all day and have answered my own question in a multitude of ways all pointing to this.... :facepalm: I should have known the answer to this question to begin with.
 
Jetta do you have an online reference chart you go to for the pH/ammonia toxicity?
 
So I was kind of right. I suppose I was comparing them to animals in the sense that when things are in plentiful supply they reproduce more. Like during mice or locust plagues. When the conditions are right - plenty of food - they just keep on multiplying. I know it's more complicated than that though.
 
But ya, you're right. just doing a bit of light reading before bed time. Most excellent article ok ammonia toxicity in fish, some of it is a review but some of it new. I'll keep the table and equation with my water testing kit from now on.

http://edis.ifas.ufl.edu/fa031
 
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Jeez you're both going to make my brain explode soon! I knew that that toxicity of ammonia was pH dependent but I didn't 100% know how.
I swear I didn't even study this much at school!
 
Since products like Prime 'detoxify' the ammonia while still leaving it available for the Bacteria to 'eat', would it be more effective to use prime daily while cycling and just the 'normal' weekly 50% water changes...instead of daily water changes? Since it leaves a large amount of Ammonia available for the bacteria, without hurting the fish?
 
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