Bioballs - why remove slowly?

[spinman]

I'm still wondering why you need to slowly remove the Bioballs while transtioning into LR rubble.

Reason is this; If you have ample Live and Base rock, and your tank has been running for several months, hasn't the beneficial bacteria seeded most of the rock by now? I would think the surface area of the rock with all its nooks and crannies is much greater than that of the bioballs.

I mean there must be a point when the rock has either met or exceeded the nitrification benefits of the Bioballs.

Mike

 

[ZoozFishMaster]

Not neccessarily. A wet/dry filter provides an excellent spot for nitrifying bacteria to colonize and therefore is extremely efficient at converting ammonia to nitrate.

Nitrifying bacteria likes two things: oxygen and water movement. There is no place in your entire system that can compete with the wet/dry for water movement and oxygen. Therefore the bacteria is going to prefer this location much more than any other location in the tank. The bacteria is a living organism...it eats and reproduces, but its numbers level off based on how much waste is being produced within the system. IMO, most of the nitrifying bacteria in your tank is housed on the bioballs, not on the live rock. Yes, there is definitely some bacteria on the live rock, but if you were to remove the bioballs all at once, it may not alone be enough to effectively consume the waste as fast as it is being produced. This would be indicated by an ammonia spike. HTH

 

[tripper]

There will only be enough bacteria on the rocks and bioballs to handle the bioload of your tank. As you add more fish, more bacteria will form due to the extra bioload. However, if the tank is stable and you remove ALL the bioballs at once, you have taken out a large percentage of the total bacteria in the tank and it will take time for the remaining bacteria to reproduce to get back to the original level. So, if you remove them slowly, you are only displacing a small percentage of the total bacterial population and the tank can compensate rather easily.

tripper

 

[spinman]

Thanks for the replies. It's starting to make more sense.

So it would seem that the LR rubble that is submerged under the sump water would offer no more benefits than the rock in the main tank, no? Just more surface area for colonization. The benefits of the 'balls appear to be because they are above the water and thus exposed to the air.

Mike

 

[lando]

If you are using fully cured LR rubble you should be able to make the transfer all at once. If not, do a quarter at a time. This will not totally wipe out your biological filtration. I replaced all of my bioballs with cured LR rubble (which is fully submerged) and my NO3 went from 15-20 to 2.5-5. Good choice.