wet/dry trickle filter

[floridagator]

howdy --

right now i have the dreaded bioballs wet/dry trickle filter. there is no way for me to remove this filter and put in a refugium without taking the tank down.. which i don't want to do.

I've read about people taking out the bioballs and replacing with live rock rubble.. is this really better? If i do that do I light the LR rubble?

another question is the tank is 6 months old - my nitrates are at 0.. I have at least 100lbs of live rock -- i'm thinking i shouldn't even mess with it but from reading on here bio's are taboo and there's going to be a nitrate explosion some day.

any suggestions are very welcome - thanks in advance

[floridagator]

bump

[2639]

Well, just like everything in this hobby, what works for one, may be disaster for another and vise versa. In other words, if you've had that setup for some time with no ill effects, why bother with it?

How long has the tank been running?

Most usually remove a few bio balls a day to slowly remove them. As far as a replacement, I'd say not to use anything. In my opinion, rock rubble would be the equivalent to bio balls.

I used to have a wet/dry filter and ran cheato in place of the bio balls with some good sized pieces of LR under the cheato. that worked really well cause I had a dayglow light on the cheato 24/7

[floridagator]

tank has been set up for 6 months.

right now the mostly FO with a couple basic soft corals.. i just upgraded the light and want to introduce more corals and it seems that your water really needs to be perfect for this so I'm a little concerned with my setup after reading so many negatives about the bio-balls.

[2639]

weeeellll..I wouldn't say it has to be 'perfect' cause my tank thrives and I'm constantly having to fiddle with something like calcium or alk LOL

What other bio filter do you have? Do you have live sand, live rock etc? If you don't have another bio filter, I'd say you'd be better off for the time being leaving the bio balls alone cause that's what is eating your nitrate cycle for you. If you have LR, then you'd be better off removing the balls over a 2 - 3 week period.

Of course, you'd want to monitor your water params the whole time you do this just to make sure that the bio filter is maintaining itself.

[2thdeekay]

Bioballs in a wet/dry filter are very good for nitrifying ammonia to nitrite and then to nitrate, and for oxygenating the aquarium, and used to be the standard in reefkeeping filtration in the 80's and early 90's. "Ammonia towers" or "trickle filters" were popular in research lab & hobbyist aquariums.

However, more recent studies have shown that with bioballs (unlike live rock or deep sand), the nitrification process is done remotely from any denitrifying bacteria, which does not aid in denitrification.

There seems to be a benefit from having the nitrification process (which produces nitrate), in close proximity to anaerobic regions in a reef tank where denitrification takes place. This allows for better denitrification, better reduction of nitrate in a reef tank. There is also additional benefit from detrivores in liverock and sand, that is missing in a "wet/dry" filter.

I think this is the currently upheld theory in the research lab, but they are still working on the "how and why".

2 cents. :)

[2thdeekay]

By the way, I agree with 2639. Good luck to you.

[toccata]

I started with a FO tank. Once I decided to move towards keeping a mixed reef and keeping all my fish, I bought lots of live rock and removed the bio balls from the filter a little at a time. Today they are gone and the system is doing fine. I already had a fuge so the wet/dry is acting like a sump now. You can do the same, but you would need to add a DSB to the wet/dry and change the flow since I think the flow might be too fast. I thought of doing this and would have drilled new holes in the wet/dry and added baffles. You would have to make sure everything is running fine however before making the wet/dry a fuge, let it run as a sump until all the rock is in place and the bio-balls are gone.

[rick s]

I agree with everyone else (except I don't feel you would "need" a DSB). I started out with the old DLS "floss roll." I slowly pulled it out and replaced it with bio-balls, and now have pulled out the bio-balls.

If you truly have zero nitrates (which is surprising), and you're testing with a reputable kit, all is fine. Keep an eye on it though.

You have 100lbs of live rock. That will become your main filter bed. So, you shouldn't "need" the bio-balls.

Most people would recommend slowly removing the bio-balls. But, that's just people's opinions. I'm personally not aware of many scientific tests being done on the subject.

Another option is this: The only reason bio-balls become "nitrate factories" is because detritus and food get caught in it, sit there, and rot. If you remove the bio-balls, say once a month, and rinse them in "old" tank water to flush away all that detritus, then they will continue to do a good job for you.

Here is one way to do so: When you are doing a water change, catch that water in a (5 gallon) bucket. Put your bio-balls in the bucket and simply "swish" them around. Hard. Then put them back in the wet/dry. No more detritus = good bio-balls.
1. You won't hurt the bacteria that is on the balls by swishing them.
2. Just make you do not use tap water. The chlorine will kill all the beneficial bacteria that is on them.

Hope this helps. . .

[toccata]

Rick,

The bio-balls just do to good of a job converting everything to nitrate, the way my filter was set up it would be very doubtful that the media was saturated with detritus. Not that is not possible, it is probably a combination of both in most cases. The reason for removing the bio-balls over a period of time is to give the tank a chance to adjust if you're adding rock and removing bio-balls at the same time.