HOB refugiums ... do they work?

[pc604]

Hi everyone,

What are your opinions regarding HOB refugiums as a means of nutrient control/export (particularly phosphates & nitrates)?

Are HOB filters generally too small to be effective? I've read that refugiums should be at least 20% of the main display, and also that a 10x-20x flow rate is generally better for macroalgae growth and prevention of buildup of excess particulates/detritus that may promote nuisance algae growth.

So here's what I think, and please correct me if I'm wrong:

There's not enough room in most HOB filters for a healthy amount of macroalgae. That being said, HOB fuges are pointless for big tanks but may be somewhat effective for smaller tanks (20 gallons or less). Also, if you do manage to stuff the HOB compartments full of macroalgae, that cuts down on the flow considerably resulting in mass buildup of oils and detritus. Now I'm not doubting all the HOB fuge users on this board as I know many of you have had great macroalgae growth in your HOBs, but I'm just curious about the before and after results as I have a 20 gallon nano myself.

Did you notice a drop in nitrates and phosphates after a HOB fuge was applied? What size tank was it applied to? If you did notice a drop in nitrate and phosphate levels, was it a result of the installation of the HOB fuge or did it result from a change in your reef husbandry routine? I bring this up because I think when most aquarists discover they have high levels of nitrates & phosphates and are considering building or purchasing equipment to help correct the problem (eg. refugium, phosban reactor...etc.), he or she will also start to change the way they do maintenance (eg. large and frequent water changes, feeding less ... etc).

Thanks!

[danny zubot]

I haven't got one yet but thanks for the facts about size and flow. I have a 65 gallon tank, so that would mean I need a 13 gallon fuge. I was debating putting some lights over my sump and planting some macro in the live rock that I have in the sump. For many people this is the only practicle method. Do you know how much light is needed for calurpa amd chaeto?

[OCDP]

This would be interesting to know... I have a HOB Aquaclear I could put some macroalgae in....

[fishface]

i've got a modified AC500 on my 25g...works great, here's a link that has alot of good info.

http://www.nano-reef.com/forums/showthread.php?s=bc578435f3e6f0d9d7c8e5431306b2f5&threadid=16635&perpage=20&pagenumber=1

darryl

[OCDP]

i think ill try it out then.. ill have to buy an ac300 or 500 though. and ill need to buy a piece of acrylic like that guy to make a divider. then buy some small pieces of LR , and the macro , thats it.. sweet deal

[pc604]

danny zubot -

http://www.wetwebmedia.com/refugfaqs9.htm
- a link to a chat session log w/ anthony calfo regarding refugiums. he recommends daylight illumination at 5000-7500K for lighting macroalgae in a fuge.

fishface - i've visited that link before, but thanks anyways :smile:
can you please give me some details on how it's working great on your system? did you notice a considerable drop in nitrates & phosphates after setting up your AC500 fuge or was it low to begin with?

ocdp - what size tank will you be putting the AC300 or 500 fuge on?

thanks guys

[fishface]

well i've pretty much had it on my tank since the beginning so i don't have too much to compare to. i've got several types of macro, LR rubble and sand and a 9" coralife freshwater plant light (24hrs). consitent tests of 0 no3 and p04 so i assume it's working well...

[bear27]

I could set you up with a peice of acrylic if you wanted

[pc604]

hi darryl,

if i do go the hob fuge route, i only have enough room on my 20 gallon to fit an AC300 (too much other stuff hanging off the tank). so i'm not too sure if it'll be as effective b/c the AC300 is quite a bit smaller than the AC500.

i'm off to home depot now to pick up a fan. it was so bloody hot today in van.

thanks

[fishface]

no kiddin' on my 25g i've got the whole back of the tank taken up by the ac500 and my skimmer but they both fit with about 2 inches left over! lucky me. don't forget you can put other accesories in your fuge (thermometer, heater etc.)

darryl

ps supposed to be hotter tomorrow!!

[OCDP]

hey guys, I am going to be using most likely an AC500 on a 20g tank.. now that someone brought it up though , I may be liimited for space as well, never crossed my mind. But at the same time you can store accessories like carbon and your heater in the AC500... so it works out alright .

if you could hook me up with a piece of acrylic that would be sweet.. either way I should be able to just pick up a piece at home depot or something like that.

im going to be getting (hopefully) some chaeto for the fuge, and ill need some rubble and some spare sand from the display. I am setting up a halide pendant in the next while here so a fuge would be a good idea to hopefully prevent, and stop any more hair algae, or other pest algae from growing.... it would be nice to hear from someone who setup a HOB AC500 fuge on their 20 gallon or whatever to see if it cured their phosphate or nitrate problems.. just so we all know .

[SeaHorse_Fanatic]

For those who are placing heaters in their HOB refugiums, just remember to set it down low because in the case of a power outage, the AC will drain & the heater might be left exposed to the air. Just something to think about.

Anthony

[fishface]

mmmmm...nice point, something to definately think of!!