[Duke79]

I realize this may be a "noob" question ... but do you unplug your filters when you do a weekly water change? I change between 25% to 30% of the water every week and the filters don't lose their prime during the water change. So I know I can keep them running ... but is it recommended?

 

[DrgRcr]

Hey Duke, as long as it doesn't lose prime from the water level being too low, I see no harm in letting them run. I do it all the time with 50%+ wc's in the tanks where my intake is low enough, never had a problem.

 

[Kerricko]

+1 I do it on my tanks with low intakes as well. Only shut them off when I clean the filters or really get into taking the tank apart for a deep clean. Don't forget to unplug the heater though.

 

[Jmanolinsky]

I unplug my filter and heater every time. Don't want sand to get stirred up or the heater to burn out.

 

[krfhsf]

I leave cans running. The splash the return makes puts O2 in the water. With the new dechlorinaters we use today for chloramies they remove alot more O2 than the old zipp drops. All HOBS, sump pumps, power heads and heaters are hooked up to a seperate power stip and it's turned off during water changes.

 

[Ron R.]

I leave my 2 2217 eheims running when I do my weekly 50% water change in my 180g tank. As long as i don't get below the intake I'm good to go. I have 2 500w titanium heaters laying directly on the sand bottom so no problem there, in fact, when I add colder water to the tank and it gets below 77 degrees, the heaters kick on during a water change.

 

[Duke79]

Thank you for taking the time to reply. I always turn the heater off when I do a water change, but have left the filters running. I didn't see any problem doing this but wanted some input from others to make sure I wasn't overlooking something.

 

[BillD]

Leaving the filter running aids in distributing the dechlor, while refilling.

 

[cichlid_baby]

I guess I am going to be in the minority here on this one...

I don't run the filters during a water change.

My reasoning.. I normally do high volume water changes.. sometimes 30% to 50% or more... which means I will be introducing a lot of new chlorinated water into the tank. Of course I always use some form of de-chlorinator to neutralize the water however, at the volume of water or the number of tanks I change.. there is no way to fully dechlorinate all the water instantly or simultaneously as it is being introduced into the tanks... and we are speaking of many 75 to 90 gal to 220 gal sized tanks and most everything in between.

What I mean is that a certain portion of that new water will not be fully treated until the tank has had a chance to completely turn over and all water has been reacted by the de-chlorinator.

Why is this important? Because if you run chlorinated water through any of your filters, you are by no means doing them any favors and are causing harm to the bacteria colonies causing them to fluctuate. Doing so can cause your bio-system to stress out.

Once the water change is completed and the de-chlorinator had had ample time to fully react with all the water does the filters get turned on.

 

[24Tropheus]

Number of tanks I change.. there is no way to fully dechlorinate all the water instantly or simultaneously as it is being introduced into the tanks... and we are speaking of many 75 to 90 gal to 220 gal sized tanks and most everything in between.

Sounds like you should get a water storage system.
Then you could use old de chlorinated/pre heated pre buffered if you like water and pump that into the tanks.
Gentlest on the fish and fastest.
And can do up to 100% change whenever you want.

Saying that its something on my wish list too.

All the best James

|My prob is if I turn anything off I get a senior moment and often forget to turn it back on. So when setting up tanks I make sure all equipment is safe to run with at least 50% of the water out. Heaters and filter intakes. That way I can do small (anything under 50% I think of as small) water changes without worrying.

 

[fmueller]

Because if you run chlorinated water through any of your filters, you are by no means doing them any favors and are causing harm to the bacteria colonies causing them to fluctuate. Doing so can cause your bio-system to stress out.

In theory that could happen, but it practice it never seems to be observed. My theory to explain that is:

1. Nitrifying bacteria are a lot tougher than we usually give them credit for.
2. There just isn't enough chlorine in tap water to make a dent in the bacteria population of a filter when kept running during a water change.

I've never switched off my filters for water changes in more than 30 years, and so far so good :thumb:

 

[cichlid_baby]

In theory that could happen, but it practice it never seems to be observed. My theory to explain that is:

1. Nitrifying bacteria are a lot tougher than we usually give them credit for.
2. There just isn't enough chlorine in tap water to make a dent in the bacteria population of a filter when kept running during a water change.

I've never switched off my filters for water changes in more than 30 years, and so far so good :thumb:

I'm not saying anyone is right or wrong here as I too have many years of fish keeping... but the only reason I've adapted this change in my practice over the years is because I do infact see that it makes a difference when I don't do it this way... versus to when I do take this extra step. I do see my tanks go through some mini-cycles after large water changes where the filter is allowed to pass mostly unchlorinated water.. in theory as well as in practice.. this is much in the same vein that we all do not recommend rinsing your filter media/sponges/pads in tap water during cleanings.. It seems to work out better for me to minimize the chorine exposure to the filters. Again.. I do this to prevent the mini-cycles that normally show up after high volume water changes.

 

[cichlid_baby]

Sounds like you should get a water storage system.
Then you could use old de chlorinated/pre heated pre buffered if you like water and pump that into the tanks.
Gentlest on the fish and fastest.
And can do up to 100% change whenever you want.

Saying that its something on my wish list too.

All the best James

|My prob is if I turn anything off I get a senior moment and often forget to turn it back on. So when setting up tanks I make sure all equipment is safe to run with at least 50% of the water out. Heaters and filter intakes. That way I can do small (anything under 50% I think of as small) water changes without worrying.

This would be the best solution... but is not practical our fishroom. We have too many tanks and not enough space to house the size of holding tank that we would need in order to do this for all our tanks. I've thought about going this route many times already but we would need a huge holding tank. Space just does not permit.

 

[fmueller]

this is much in the same vein that we all do not recommend rinsing your filter media/sponges/pads in tap water during cleanings.

Actually, I do rinse all of my sponge filters in tap water. The big sponge mats that filter my 240G are taken outside in summer and cleaned with plenty of cold tap water from the garden hose. It has never caused my fish a problem, and I certainly don't observe mini cycles after cleanings.

Of course your tap water could contain unusually large amounts of chlorine, plus it's always better to err on the side of caution, but I still believe that in this regard a lot of people make much ado about nothing. Just my 2c.