Biofiltration

[Guest Reef Nuby]

My family and I have recently set up a 55g SW reef tank about 5 months ago. We have somewhere around 50-60lbs of various types of live rock. Aprox. 30lbs of wich we bought uncured to cycle our tank.

 

We use a Rena XP3 canister type sump with as much bio media I could stuff in it.

 

I still have plenty of room for more live rock in the tank, but we enjoy being able to easily see our fish and thier other tank mates.

 

Should we add more? Our water perameters are "pristine" according to the master test kit i bought. The only fluctuation is the salinity. but its very minor and the local SW aquarium experts say it has to do with the type of hydrometer im using.

 

Also, why wouldnt i pack the various trays of my canister filter with pieces of live rock instead of some foam or rock media i have to change in 2-3 months?

Edited August 26, 2007 by Reef Nuby

[Rascal]

The old rule of thumb I think used to be 1.5 - 2 lbs live rock per gallon, but I think many reefers (including yours truly) nowadays are going with more like 1 lb per gallon, if that. As long as the rock is nice and open and porous and you have good flow (min 15-20x turnover for softies and LPS and at least 30x turnover for SPS IMO) you are probably fine with 50-60 lbs LR in the display.

 

As for your second question, umm . . . IMO you are on the right track.

Also, why wouldnt i pack the various trays of my canister filter with pieces of live rock instead of some foam or rock media i have to change in 2-3 months?

 

The next question is why have a canister filter at all? Why not just have a true sump and if you wanted more bio-filtration than you have in your display, add some live rock there?

 

I have to confess I am surprised that you have had your tank running for 5 months with a canister filter packed with bio-media and your water parameters still test pristine. Conventional wisdom says your nitrates would be climbing by now.

 

Still, to answer your question, I can't think of any reason why one would want to use foam or some non-marine rock media instead of live rock.

[Guest Reef Nuby]

Indeed Rascal.

 

the only reason why i used the canaster filter (rena xp3) was because i was told it would do rather well with my smaller sized 55g. also the manufactuer (or the store i bought it from, not sure which no that i try to recall) claimed that the various forms of media that rena sold for its several trays would also work as a skimmer. (now that i understand what skimming is....i really cant see how a canaster filter would do it).

 

but as i siad my perameters are right on. it could have something to do with the fact that i do have several forms of biomedia in it and some "magic" bio stone that is specifically made to reduce amonia (im not sure how, other than using bacteria i already have in my tank).

 

or maybe in just setting myself up for an enevitable desaster?

 

oh yes....to answer why one would use some form of foam product as biomedia.....

 

im not sure what its really made of, but when i bought the filter, i purchased all the differant types of media they had for the extra trays in the filters "sump case". they look like little stars and "coosh balls", and other kids or cats toys, but i thought the folks at the local pet shop knew what they were talking about

[fishcam]

(min 15-20x turnover for softies and LPS and at least 30x turnover for SPS IMO)

 

Whoa... 30x? I'm setting up a 55+20g, and I've got a 900gph return... thats only 16x or so return... if you dont count the sump gallons. So I could be running two of these things? Is that what you're running (ish)?

 

d

[yauger]

Whoa... 30x? I'm setting up a 55+20g, and I've got a 900gph return... thats only 16x or so return... if you dont count the sump gallons. So I could be running two of these things? Is that what you're running (ish)?

 

d

 

also keep in mind with your return if you have PVC elbows or any type of wave making device (SWID) your flow will greatly decrease, in addition to the height decrease in flow.

for example my return is by a MAG 9.5 (@ 3 ft = 850GPH) with a head of 3 feet, running 6 elbows in the return drops the return rate to roughly 600GPH.. I'm assuming the elbows decrease the flow by 40 GPH each. The decrease of the elbows might be more or less but from what see in my system thats my guess...

[Brian Ward]

Don't confuse total turnover with movement through the filter. You need approx 10x turnover through your filter, the water through the fuge you generally want to move slower - allowing the plant material to metabolize the chemicals. You create the additional turnover through the use of closed loops and circulation pumps (tunze turbelle 6101 is a popular model). For an SPS-dominated tank, 50x turnover isn't unheard of - you also want to create varying currents in the tank. corals seem to like this since it mimics the shallow waters they typically inhabit.

~Brian

 

Whoa... 30x? I'm setting up a 55+20g, and I've got a 900gph return... thats only 16x or so return... if you dont count the sump gallons. So I could be running two of these things? Is that what you're running (ish)?

 

d

[yauger]

Whoa... 30x? I'm setting up a 55+20g, and I've got a 900gph return... thats only 16x or so return... if you dont count the sump gallons. So I could be running two of these things? Is that what you're running (ish)?

 

d

 

This calculation also includes the turnover rate of your powerheads....

[Brian Ward]

Indeed Rascal.

 

the only reason why i used the canaster filter (rena xp3) was because i was told it would do rather well with my smaller sized 55g. also the manufactuer (or the store i bought it from, not sure which no that i try to recall) claimed that the various forms of media that rena sold for its several trays would also work as a skimmer. (now that i understand what skimming is....i really cant see how a canaster filter would do it).

 

but as i siad my perameters are right on. it could have something to do with the fact that i do have several forms of biomedia in it and some "magic" bio stone that is specifically made to reduce amonia (im not sure how, other than using bacteria i already have in my tank).

 

or maybe in just setting myself up for an enevitable desaster?

 

oh yes....to answer why one would use some form of foam product as biomedia.....

 

im not sure what its really made of, but when i bought the filter, i purchased all the differant types of media they had for the extra trays in the filters "sump case". they look like little stars and "coosh balls", and other kids or cats toys, but i thought the folks at the local pet shop knew what they were talking about

 

As far as the orginal topic post, I don't believe you can have "too much" biological filtration. My understanding of how this works is that the bacteria levels will adjust themselves as the necessary chemicals are available for processing - think darwinian survival of the fittest. If you introduce too much bacteria, the ones not able to gain enough chemicals to keep going will die off, providing ammonia, etc for the other bacteria. As more chemical is available and the bacteria reproduce, there will be an increase the total bacteria population. This is why you don't want to introduce too many fish into your tank at once - the bacteria will not be able to keep up with processing the chemicals produced by the fish since it takes time for them to reproduce.

~Brian

 

EDIT: There will be a maximum bacteria population your setup can handle - that is where the 1.5 lbs/gal rule came from. That's approximately the amount of rock required to support the bacteria population required for the fish that size tank can "handle". There are other devices such as skimmers and whatnot that will help remove toxins, allowing you to increase the bioload of the tank while not increasing the amount of rock for the bacteria to live in.

Edited August 27, 2007 by Brian Ward

[extreme_tooth_decay]

Whoa... 30x? I'm setting up a 55+20g, and I've got a 900gph return... thats only 16x or so return... if you dont count the sump gallons. So I could be running two of these things? Is that what you're running (ish)?

 

d

 

 

 

Some folks run more, some run less. I always chuckle when I see such big numbers.

 

I don't have SPS, but do have a vey successful softie/LPS tank, and I have about 6x.

 

The vast majority of the years I have had this tank set up I have had no algae problems

and uncontrollable coral growth

 

My advice, as always, is to experiment and see what works for you.

 

tim

Edited August 27, 2007 by extreme_tooth_decay

[Guest Reef Nuby]

thanks for the advice and overall wisdom of your experiances. (even you folks who tend to run off topic )

 

as for my canister filter, the flow rate on my "flow meter"(which i have set on my return line and not the intake) says my overall turnover in my tank is just between 9 and 10 times an hour, estimating i have only actually 45 gallons of water in my tank since the live rock, substrate, and inhabitants take up so much room. also my tank is not filled completely from top to bottom, hence my water line is aprox 2" from the top of my tank.

 

i have two 45g max ph whisper power heads with deflectors on the opposite side of the tank my return tube (with holes along its length) to create movement. which as i understand it is the way i should do it.

 

if there is a better way for me to set my tank up, please blast me with some knowledge.

 

oh, and i am not currently using a skimmer. i had a used berlin that had a leak on the bottom of the canister, and it really didnt fit properly inder my tanks hood or head piece.

 

ive read of people instituting a skimmer/sump with more live rock in the sump, but i have no idea how its done. im a pretty hands on type of guy, and im sure i could design something, if one of you could please explain how such a process would work, and/or how a skimmer works exactly.

 

thanks, norm

 

ps, sorry no pics yet. it seams the site admin isnt allowing me to do so...yet???

[Rascal]

Some folks run more, some run less. I always chuckle when I see such big numbers.

. . .

My advice, as always, is to experiment and see what works for you.

 

There is certainly more than one way to skin a cat (not that I condone such behavior ). I tend to favor higher flow rates. My recommendation for softies/lps may be higher than what is used by most. It is just based on my experience with my 1st tank, which was a softie/lps tank. I started off at 10X turnover and gradually increased to around 20X, and I believe this had a markedly positive effect on my corals. For an SPS dominated tank I don't think 30X total turnover is at all excessive, though I'm sure there are plenty of reefers who have achieved success with less.

 

The only thing I would add to the advice of experimenting to see what works is to take a look at as many other systems as possible, both in person and online, before deciding exactly what type of tank you want and then thinking about how best to create that environment. Most of us will never have a "Tank of the The Month", but there is a nevertheless a lot to learn from looking at these very successful systems: http://reefkeeping.com/issues/subject/totm.php

 

ive read of people instituting a skimmer/sump with more live rock in the sump, but i have no idea how its done. im a pretty hands on type of guy, and im sure i could design something, if one of you could please explain how such a process would work, and/or how a skimmer works exactly.

 

You might find this site helpful if you havn't already found it: http://www.wetwebmedia.com/plumbingmarart.htm

Pretty much all of the set-up articles and FAQs: http://www.wetwebmedia.com/marine/index.htm

 

You could read forever, but probably the best way to understand it is to see it in person. I don't know if there are any WAMAS members near you, but maybe a road trip to a good LFS like Blue Ribbon Koi is in order. Atlantis in Richmond may be closer to you.

Edited August 27, 2007 by Rascal

[Guest Reef Nuby]

thanks again rascal.

 

im on my way out the door as soon as i send this reply