Cycling A New Filter.

[Min8040]

My tank is cycled and has a internal filter. I have just purchased a new external filter (still waiting on media).
My question is, how long will this new filter take to cycle with the old internal one still running in the tank???
The external canister is a sunsun hw-302.

Thanks, Min.

 

[roadmaster]

My tank is cycled and has a internal filter. I have just purchased a new external filter (still waiting on media).
My question is, how long will this new filter take to cycle with the old internal one still running in the tank???
The external canister is a sunsun hw-302.

Thanks, Min.

I would give it a couple weeks minimum.

 

[KittyKat]

4 weeks if you want to risk it, 6 weeks to be safe. Alternatively, move all old media into new filter instead.

 

[anon02]

I would say it will be more like 2-3 months if you just run it alongside a mature filter. If you remove all of the mature media from the old filter and put it into the new filter you should be able to move your existing live stock over right away, I would give it a fortnight of zero toxin water tests before adding any new fish

 

[Min8040]

My tank is cycled and has a internal filter. I have just purchased a new external filter (still waiting on media).
My question is, how long will this new filter take to cycle with the old internal one still running in the tank???
The external canister is a sunsun hw-302.

Thanks, Min.

I would give it a couple weeks minimum.

I thought i`d ask here as my lfs said 1 week will be enoungh. I`ll go longer than a few weeks, maybe 2 months.

 

[Min8040]

4 weeks if you want to risk it, 6 weeks to be safe. Alternatively, move all old media into new filter instead.

I can`t move the media as it is needed in this filter for a different tank.

I would say it will be more like 2-3 months if you just run it alongside a mature filter. If you remove all of the mature media from the old filter and put it into the new filter you should be able to move your existing live stock over right away, I would give it a fortnight of zero toxin water tests before adding any new fish

This is what I`ll be doing. I thought 2 months would be good, maybe i`ll let it go for 3 just to be safe. As for media, i need it in the filter its already in. Its for another tanks. I won`t be adding anymore fish to this tank but i`ll still keep checking toxin levels daily for a while.

 

[Min8040]

Thanks to everyone for your replies. Looks like I`ll let it run alongside my other filter for 2-3 months just to be on the safe side. My son would get very upset with me if I did something wrong and made his fish die.
Another question. If I do a 50% water change (Its a 150 liter tank) how long should I wait before testing for toxins? When I do 20% I normally wait20-30 minutes. Is this ok or not?

Any and all comments appreciated.

Min.

 

[Tizer]

Shouldnt really be any reason to test after a water change as you should have tested it before the water change.

if you get a reading of say 0.5 ammonia and do a 50% water change, then logic tells you its going to be 0.25 afterwards. Do the math then retest 24 hours later.

if you really want to test afterwards, then 5/10 minutes should be enough for a good old mix up, many people will say you can do it straight away.

 

[roadmaster]

4 weeks if you want to risk it, 6 weeks to be safe. Alternatively, move all old media into new filter instead.

I can`t move the media as it is needed in this filter for a different tank.

I would say it will be more like 2-3 months if you just run it alongside a mature filter. If you remove all of the mature media from the old filter and put it into the new filter you should be able to move your existing live stock over right away, I would give it a fortnight of zero toxin water tests before adding any new fish

This is what I`ll be doing. I thought 2 months would be good, maybe i`ll let it go for 3 just to be safe. As for media, i need it in the filter its already in. Its for another tanks. I won`t be adding anymore fish to this tank but i`ll still keep checking toxin levels daily for a while.

Should not take two months but I do not blame you for being cautious.
Bacteria ,once established has no problem multiplying or transferring, and colonizing another filter so long as surface area is available and conditions are favorable.
Recently set up 55 gallon with mature sponge filter and new Aquaclear 110. Placed four Bristlenose in the tank the same day and remnoved the sponge filter after three weeks.No problems, and fish have since spawned and am now going to use same mature sponge filter to set up 29 grow out tank for the bristlenose fry along with new aquaclear 70 filter .
Leaving the two filters to run together for months is near failproof but in my view,expierience,, not necessary. Opinion's vary.

 

[KittyKat]

Should not take two months but I do not blame you for being cautious.
Bacteria ,once established has no problem multiplying or transferring, and colonizing another filter so long as surface area is available and conditions are favorable.
Recently set up 55 gallon with mature sponge filter and new Aquaclear 110. Placed four Bristlenose in the tank the same day and remnoved the sponge filter after three weeks.No problems, and fish have since spawned and am now going to use same mature sponge filter to set up 29 grow out tank for the bristlenose fry along with new aquaclear 70 filter .
Leaving the two filters to run together for months is near failproof but in my view,expierience,, not necessary. Opinion's vary.

Enough bacteria for one or two fish in a large tank does not take long.. but for a decent stock, it does take a while.

 

[Min8040]

Maybe I should have mentioned this, the tank is a 3 foot (150 liters) and has 6 guppies and 3 mollies. No live plants, just plastic fantastic.

 

[KittyKat]

Maybe I should have mentioned this, the tank is a 3 foot (150 liters) and has 6 guppies and 3 mollies. No live plants, just plastic fantastic.

That stocking won't produce much ammonia, so it when you move the filter over to the new tank, you should still stock slowly and watch readings carefully.

 

[roadmaster]

Maybe I should have mentioned this, the tank is a 3 foot (150 liters) and has 6 guppies and 3 mollies. No live plants, just plastic fantastic.

That stocking won't produce much ammonia, so it when you move the filter over to the new tank, you should still stock slowly and watch readings carefully.

+one slow stocking is always best way forward.
Quarantine new fishes is also desireable.