Low Nutrient Tanks & Refugiums

[vitodog]

Anyone maintain a "Low Nutrient Tank" and are able to keep a healthy refugium? If so, what are your secrets and what macro algae have you been successful with? I have had problems with Bryopsis, GHA and cyano in the past which were due to a combination of my light schedule and over feeding. I corrected my light schedule and made changes to what and how much I was feeding and have pretty much got control of the nuisance algae. I have since been able to maintain nitrates near zero and phosphates at or near zero (Hanna Phosphate Checker) for the last 6 months. However, I have been unable to keep macro algae. Before I lowered my nutrient intake, I successfully maintained chaeto as well as mangroves in my refugium. Any thoughts, suggestions and or advise? Thank you.

[Randy Holmes-Farley]

Depending on how low you go, it may be hard to keep macroalgae. ULNS systems are basically designed to starve corals and microalgae, so it is not surprising that you'd also starve macroalgae, especially if they get less light than the main tank.

IME, caulerpa racemosa can outcompete chaetomorpha, so it may do better at lower nutrient levels than does chaeto.

[vitodog]

Originally Posted by Randy Holmes-Farley

Depending on how low you go, it may be hard to keep macroalgae. ULNS systems are basically designed to starve corals and microalgae, so it is not surprising that you'd also starve macroalgae, especially if they get less light than the main tank.

IME, caulerpa racemosa can outcompete chaetomorpha, so it may do better at lower nutrient levels than does chaeto.

Thanks Randy. My fish don't seem to mind one way or the other regarding my nutrient levels and with the exception of some of my LPS, the corals don't seem to mind either. When I purchased my currant sump, it came with a chamber for a refugium. Right now, my tank looks pretty healthy. So, maybe I don't really need macro algae. I might try the racemosa you suggested though. Thanks again.

[Randy Holmes-Farley]

Good luck and happy reefing.

[tmz]

The macro algae is useful for providing some O2 during opposite photo periods even if it's not needed for nutrient reduction,imo. I keep chaetomorpha reasonably well lit;it exhibits slow growth in a realtively low nutrient system( PO3<.05ppm pr hanah colorimeter; NO3 around .2ppm ) If the PO4 drops lower the chaeto wanes.; some lps don't like "ultra low levels" either. A little iron dosing seems to help it.

[vitodog]

Originally Posted by tmz

The macro algae is useful for providing some O2 during opposite photo periods even if it's not needed for nutrient reduction,imo. I keep chaetomorpha reasonably well lit;it exhibits slow growth in a realtively low nutrient system( PO3<.05ppm pr hanah colorimeter; NO3 around .2ppm ) If the PO4 drops lower the chaeto wanes.; some lps don't like "ultra low levels" either. A little iron dosing seems to help it.

Thank you TMZ. It seems that a little PO4 in the tank is not necessarily a bad thing. My PO4 has consistently tested 0.00, using the hanna colormeter. Would the iron dosing be a safe way to raise my PO4 a little? I can test for iron (Seachem) although I don't have a lot of faith in the reliability of these test kits (for iron). I've been running bio pellets since may of this year along with Rox 0.8 (24/7). I also run my skimmer 24/7. Thank you.

[tmz]

No iron won't raise PO4;food will. The new Red Sea iron test works ok but I can't swear to it's accuracy. In my experience a little PO4 is ok as is a little nitrate but it depends on what you are trying to accomplish.

[Randy Holmes-Farley]

I wouldn't bother testing for iron. You probably want it lower than the detectable limit anyway.

[vitodog]

Originally Posted by tmz

No iron won't raise PO4;food will. The new Red Sea iron test works ok but I can't swear to it's accuracy. In my experience a little PO4 is ok as is a little nitrate but it depends on what you are trying to accomplish.

Thanks TMZ. I understand the relationship between food and PO4, and how iron might help promote macro algae growth. I would like to keep my nutrient levels on the low side and still be able to maintain some macro algae in my refugium. When I did have healthy macro algae (chaeto & mangroves) in my refugium, I also had infestations of nuisance algae. So, I guess what would like to accomplish is a healthy refugium without any nuisance algae in my D/T. Sounds like I have to find that balance between feeding too much, too little and just the right amount. Thanks again TMZ. Your help/advise is always appreciated.

[tmz]

You are welcome . I think that balance is a very fine line. I want it clean but not anemic. Since I feed heavily I think I get some PO4 and NO3 at least for some of the time but I don't have nuisance algae except for a wisp or patch now and then . Some microalgae on the glass requires a magnet sweep once a week or so.

[bobgrif]

Originally Posted by vitodog

Anyone maintain a "Low Nutrient Tank" and are able to keep a healthy refugium? If so, what are your secrets and what macro algae have you been successful with? I have had problems with Bryopsis, GHA and cyano in the past which were due to a combination of my light schedule and over feeding. I corrected my light schedule and made changes to what and how much I was feeding and have pretty much got control of the nuisance algae. I have since been able to maintain nitrates near zero and phosphates at or near zero (Hanna Phosphate Checker) for the last 6 months. However, I have been unable to keep macro algae. Before I lowered my nutrient intake, I successfully maintained chaeto as well as mangroves in my refugium. Any thoughts, suggestions and or advise? Thank you.

Try this link it will explain what macros to get if your tank has continuously low nutrients.

http://www.reefcleaners.org/index.ph...=50&Itemid=143

Chaeto and Caulerpa. Do well with high nutrients and will recede if they do not have high nutrients until the levels go up. I have found that if they never go high enough Caulerpa will die off and Chaeto will break apart for the most part. Since I have very low nutrients due to various reason I tend to stick to Macro's that require very little nutrients or ones that can survive with little to none.

[vitodog]

Originally Posted by bobgrif

Try this link it will explain what macros to get if your tank has continuously low nutrients.

http://www.reefcleaners.org/index.ph...=50&Itemid=143

Chaeto and Caulerpa. Do well with high nutrients and will recede if they do not have high nutrients until the levels go up. I have found that if they never go high enough Caulerpa will die off and Chaeto will break apart for the most part. Since I have very low nutrients due to various reason I tend to stick to Macro's that require very little nutrients or ones that can survive with little to none.

Wow bobgrif, what a surprise to see something I posted almost a year ago re-appear. I purchase from ReefCleaners all the time. However, I never noticed the info on the low nutrient macros. Thank you.

[tankmates]

I have high nutrient issue right now..running gfo, feeding limited to once a day..mysis sometimes, ocean nutrition pellets other time and once in a while frozen cyclopeeze...I run skimmer 24x 7, bio pellets 24x7 , gfo 24x7 ...water change every 2 weeks...my phosphates checked with hanna are at .18 ..which is too high right now....out of ideas what else I should be doing....I have remote dab in Refugium...maybe that is trapping phosphates..shall I take that off...do not mean to high jack thread...but I thought my problem is same....sps are going downhill

[bertoni]

I'd replace the GFO more frequently. With the phosphate level that high, you might need to change the media every day for a couple of days. If you measure the phosphate level of the reactor output, and it matches the level in the tank, the media is shot. I might stop feeding for a few days, while trying to sort out the problem, too.

[tankmates]

i will try this schedule for next few days...will limit feeding to once a couple of days..will also do another water change tomorrow to start with this schedule.

[bertoni]

Okay, sounds like a useful experiment!