Don't do water changes while cycling a tank! MYTH?

[PureColorDesigns]

Have been cycling my 20Gallon tank for 5 weeks and nitrites and nitrates are still stuck.

I have considered a water change but was talked out of it.

This morning MarineDepot.com sends a newsletter stating this:

 

"This myth says that performing water changes actually extends the time it takes to cycle an aquarium. Water changes are beneficial when cycling an aquarium as they dilute ammonia and nitrite. Reducing the amount of ammonia or nitrites won't slow the cycle down. It is said that removing water also removes beneficial bacteria. Most of the bacteria in an aquarium will reside on the substrate (rocks, sand and gravel), so removing water will not affect the bacterial load."

 

Link to the article!

 

What does everyone think?

[herranton]

What are your nitrites?

You can do your first water change after they are zero. Sometimes it just takes time. Be patient. 5 weeks isn't unheard of.

[PureColorDesigns]

What are your nitrites?

You can do your first water change after they are zero. Sometimes it just takes time. Be patient. 5 weeks isn't unheard of.

 

To High to read!

[altolamprologus]

Reducing the amount of ammonia and nitrite during the cycle reduces the bacterial load needed to process it, thus reducing the amount of bacteria present when the cycle is over. So you you have to stock extra slow and it increases the risk of having ammonia spikes when adding livestock. It's best to let the cycle run it's course, except when ammonia approaches 6 ppm

[herranton]

To High to read!

Are you sure you are doing the test right? Maybe you have some bad tests. If it's not too inconvenient, try to take some of your water to your lfs and have them test it for you. I have a hard time believing that a tank that has been cycling for 5 weeks would have the nitrate off the chart.

[PureColorDesigns]

Reducing the amount of ammonia and nitrite during the cycle reduces the bacterial load needed to process it, thus reducing the amount of bacteria present when the cycle is over. So you you have to stock extra slow and it increases the risk of having ammonia spikes when adding livestock. It's best to let the cycle run it's course, except when ammonia approaches 6 ppm

 

 

My ammonia was at 8ppm in the beginning but now is at .25ppm. Could my ammonia spiking this high in the beginning have cause such a long cycle?

[herranton]

Reducing the amount of ammonia and nitrite during the cycle reduces the bacterial load needed to process it, thus reducing the amount of bacteria present when the cycle is over. So you you have to stock extra slow and it increases the risk of having ammonia spikes when adding livestock. It's best to let the cycle run it's course, except when ammonia approaches 6 ppm

Yes and no.

 

The amount of bacteria will stabilize at the current bioload of the tank. If you leave a tank empty for too long after the cycle, there could be very little bacteria in the tank because their food supply is dried up. I wouldn't personally do WCs during a cycle, but I really don't think that it would make that much difference. As soon as you add a fish/snail/hermit/shrimp, the population will attempt to stabilize and reach equilibrium again.

 

You should always stock slow and responsible. I don't think you would need to go any slower depending on how you cycled.

[altolamprologus]

My ammonia was at 8ppm in the beginning but now is at .25ppm. Could my ammonia spiking this high in the beginning have cause such a long cycle?

Yes, at 6 ppm and above, the beneficial bacteria start to die. Even though that's what they use as a food source, ammonia is still toxic to them in large enough quantities. This is the only case in which I recommend a water change during the cycle.

 

Yes and no.

 

The amount of bacteria will stabilize at the current bioload of the tank. If you leave a tank empty for too long after the cycle, there could be very little bacteria in the tank because their food supply is dried up. I wouldn't personally do WCs during a cycle, but I really don't think that it would make that much difference. As soon as you add a fish/snail/hermit/shrimp, the population will attempt to stabilize and reach equilibrium again.

 

You should always stock slow and responsible. I don't think you would need to go any slower depending on how you cycled.

I guess you're right it wouldn't make too much of a difference. I still think it's better to let "nature" run its course and the tank do its thing undisturbed, except in extreme circumstances.

[seabass]

I'd like to see their data. Here is mine. Basically my testing showed that doing water changes can actually extend the time it takes for ammonia to start reducing on its own; in addition, it did little to lower the ammonia level.

 

My take on water changes, when the nitrogen cycle is still becoming established, is that you should hold off until ammonia starts dropping by itself. After it starts to decline, water changes become beneficial.

[banshee]

I'd like to see their data. Here is mine. Basically my testing showed that doing water changes can actually extend the time it takes for ammonia to start reducing on its own; in addition, it did little to lower the ammonia level.

 

My take on water changes, when the nitrogen cycle is still becoming established, is that you should hold off until ammonia starts dropping by itself. After it starts to decline, water changes become beneficial.

 

This. My cycle was similar to yours with all readings off the chart. I started doing 2 gallon water changes every other day until they were back on the low end. Cycle finished quickly after that and then I stocked pretty quickly with no mini cycles. Same thing with my pico.

[Whys]

Reducing the amount of ammonia and nitrite during the cycle reduces the bacterial load needed to process it, thus reducing the amount of bacteria present when the cycle is over. So you you have to stock extra slow and it increases the risk of having ammonia spikes when adding livestock. It's best to let the cycle run it's course, except when ammonia approaches 6 ppm

 

Agreed. It's akin to saying: eating half your apples before they are ripe doesn't make them ripen any slower.

 

[Seacret]

I'd like to see their data. Here is mine. Basically my testing showed that doing water changes can actually extend the time it takes for ammonia to start reducing on its own; in addition, it did little to lower the ammonia level.

 

My take on water changes, when the nitrogen cycle is still becoming established, is that you should hold off until ammonia starts dropping by itself. After it starts to decline, water changes become beneficial.

If my ammonia level is dropping now and my nitrates/nitrites are still high is it a good time to start water changes?

[seabass]

Yep, you won't be extending the cycle any by performing a water change while your tank has declining ammonia but still has detectable nitrite. Just wait until ammonia becomes undetectable before adding livestock.

[Seacret]

Yep, you won't be extending the cycle any by performing a water change while your tank has declining ammonia but still has detectable nitrite. Just wait until ammonia becomes undetectable before adding livestock.

How frequently would you recommend a water change for an 8 gallon, and how much 10%?

Thanks for the reply!

[seabass]

For an 8 gallon tank, I'd chage a gallon every week. You can adjust this depending on your tank's bio-load and nutrient levels.

[jestep]

If you start doing water changes before ammonia begins to lower I've seen them take months. Also, if the rock itself isn't fully cured, it can be a significant ammonia source for a lot longer than the ~30 days required to cycle the tank. It's being processed at that point, but still is a nutrient contributor to the tank.

[moldycheese432]

Excessively high nitrite could be toxic, water changes might be justified on the basis that toxic levels of nitrite are growth inhibitory

[seabass]

Read this: http://www.reefkeeping.com/issues/2005-06/rhf/

 

"In reality, nitrite probably is not toxic enough to warrant measuring in most marine systems."

- Randy Holmes-Farley

[Azedenkae]

I wouldn't go as far as to say 'don't do water changes during a cycle', but lol that article is just wrong in terms of water changes. Water changes, by removing ammonia, nitrite (and nitrate), along with whatever other nutrient WILL most likely slow a cycle down, as that is taking away food for the microbes to feast upon. Yes so long as you have it in there, the microbes will eventually grow enough anyways, but it's all about chances.

 

Imagine a sushi train, and you are waiting for a dish to arrive. Each time you eat, you grow a bit. Now if the sushi train is full of dishes, you'll be able to eat more. If it isn't, there may be time between meals. It's not exactly that, but it's basically that. Of course, by chance the microbes could just happen to continuously get 'fed', but there's better chances without changing out water.

 

Additionally, it is also important to gauge how well the microbe is dealing with ammonia and stuff. If you are the one taking them out and perhaps not testing things well, then it is hard to determine if it is the microbes you are growing that are breaking down the waste, or if it is due to your water changes.

 

I am not saying to avoid water changes completely. If parameters are too high, then that would inhibit growth and can even lead to mortalities. So then water changes are good. But otherwise, why bother? Sure it may not slow down the cycle, but it also might. Not doing a water change ensures that there's no change it may slow down the cycle (again, assuming your parameters are not extremely high).

 

[EDIT]

 

Just to be clear, ammonia for example, has to be reaalllllyyyy high for it to take effect. And then even higher for mass mortalities of microbes. Like, WAY off the charts. WAYYYYY off the charts.

 

Otherwise if your cycle is stalling, then you simply do not have enough microbes breaking things down yet. And that may simply be because they don't have enough nutrients to sustain them. And I don't mean just nitrogen or whatever. I mean carbon, phosphorous and everything else that makes up those microbes. A lot of people just dose ammonia and then never see it drop because of this (also assuming they started with cured base rock or something similar).

[Tamberav]

Have been cycling my 20Gallon tank for 5 weeks and nitrites and nitrates are still stuck.

I have considered a water change but was talked out of it.

This morning MarineDepot.com sends a newsletter stating this:

 

"This myth says that performing water changes actually extends the time it takes to cycle an aquarium. Water changes are beneficial when cycling an aquarium as they dilute ammonia and nitrite. Reducing the amount of ammonia or nitrites won't slow the cycle down. It is said that removing water also removes beneficial bacteria. Most of the bacteria in an aquarium will reside on the substrate (rocks, sand and gravel), so removing water will not affect the bacterial load."

 

Link to the article!

 

What does everyone think?

 

 

I would say... it depends....

 

Doing water changes during a cycle is known as a "soft cycle". I did this with some uncured live rock to keep the hitchikers alive... basically water changes to keep ammonia around 0.25. My cycle was very short, about 2 weeks... but that had more to do with just how much live bacteria and organisms were already on the rock.

 

Meanwhile I did no water changes on dry rock and it took about 5 weeks. Since the rock started out dry... it had a long way to build up the bacteria needed to process waste.

 

 

I personally do no water changes on dry rock, soft cycle uncured rock, and cured rock... I would keep around/under 2ppm ammonia. This is just what I have found works best for me.

[Najay343]

I just finished cycling my tank. My ammonia peaked at 8ppm before I removed the raw shrimp and added bio-spira. Two weeks into the cycle I still had 3ppm ammonia and 80ppm nitrate. I ended up purchasing "Deep Blue Professional ADB41005 Nitrate Remover Pad, 18 by 10-Inch" on amazon and after one week my numbers were 0 across the board. I technically didn't even have to do a water change at all.

[Azedenkae]

I guess I should chime in too. I just cycled my aquarium using uncured dry rock and sand, it is only a 10g nano. Used pureed seafood and didn't do any water changes. By day 9 it was fully cycled.

 

I agree that if you want to keep certain organisms alive, a water change MAY be necessary, but it really is an exception than the norm. Or should be anyways.

[tibbsy07]

Why bother changing your water during the cycle? You want your bacterial levels to be at their peak. Doing water changes and removing their nutrient source will slow them down. It's extra work that is completely unnecessary.

 

When you cycle your tank, LEAVE IT ALONE. Don't turn the lights on, don't change the water. Sure you CAN, but why? Just let it ride.

[Azedenkae]

Why bother changing your water during the cycle? You want your bacterial levels to be at their peak. Doing water changes and removing their nutrient source will slow them down. It's extra work that is completely unnecessary.

 

When you cycle your tank, LEAVE IT ALONE. Don't turn the lights on, don't change the water. Sure you CAN, but why? Just let it ride.

Defo. As with anything else in the hobby, if it ain't broken don't fix it lol.

[seabass]

Doing water changes during a cycle is known as a "soft cycle". I did this with some uncured live rock to keep the hitchikers alive... basically water changes to keep ammonia around 0.25. My cycle was very short, about 2 weeks... but that had more to do with just how much live bacteria and organisms were already on the rock.

Look at my data again: http://www.nano-reef.com/topic/206500-part-2-water-changes-during-the-cycle/

 

In the container that I performed 25% water changes each day, the ammonia level was not substantially reduced compared to the container that received no water changes at all (and the ammonia peaked at the same level). Water changes only temporarily lowered the ammonia level (by the percentage of the water change). However, ammonia levels quickly returned to their previous level or continued to increase until the nitrifying bacteria became established. Plus, ammonia levels remained high for longer in the container that received daily water changes.

 

Obviously water changes lowered nitrate levels. Plus they lowered the peak level of nitrite. However, we aren't as interested in these levels as their toxicity is much less than for ammonia.

 

A better method to soften the cycle would be to introduce a working biofilter, to help process the ammonia as it's produced. Another method would be to introduce a nitrifying bacteria culture (like Dr.Tim's One and Only) to raise bacteria populations.