Reducing nitrates and phosphates?

[mike550]

Okay. My nitrates are running 15-20 and phosphate around 0.14 for my 120G reed tank. So I think it’s a bit high. I’d like to be 5-10 nitrate and low as possible for phosphates

I realize water changes won’t get me to my target as a long term solution. Rather not resort to chemical solutions. So what options do I have for long term reduction? Is it live rock in sump, somehow increase bacteria? Thanks in advance.

 

[Greg P]

How old is your tank?
Do you have any corals, and if so how many/how big?
Corals will process NO3 and PO4, but algae will as well.
Live rock on it's own will not process either and IMHO neither will bacteria, at least not in the numbers you are concerned about.

The more mature your tank is in conjunction with how many corals you have, the more of these nutrients the tank as a whole will process without you having any significant algae issues.

 

[jformani]

How often do you do water changes? They help. Reactors also help. You can add a reactor and GFO to lower phosphates.

 

[mike550]

@Greg P @jformani thanks for your replies. I change 20G every two weeks but increased it more recently to weekly when I saw my nitrates and phosphates rose.

The 120G tank is around six months old and Im still stocking. Just taking my time. Eight fish (2 clowns, blenny, goby, chromis, blue tang, rabbitfish, and a dwarf flame angel) also have a blue sea star, BTA, and decent size (5”) maxima clam. Fish probably average 2-3”. On coral side, green star polyp (5-6 sq inches), Kenya tree (4-5” tall), frogspawn (baseball size), zoanthid (small) and a trachyphilla (small).

 

[Greg P]

You don't have a significant amount of coral, so not much nutrient processing going on.
Keep testing your NO3 and PO4 weekly, or more, and see if it's stable, rising, or maybe even lowering.
After you get a grip on the weekly averages you can decide if you really need to intervene or just let it ride.

BTW, are the levels you have now causing any issues you are concerned about, or are you just testing to know what's going on?

 

[mike550]

You don't have a significant amount of coral, so not much nutrient processing going on.
Keep testing your NO3 and PO4 weekly, or more, and see if it's stable, rising, or maybe even lowering.
After you get a grip on the weekly averages you can decide if you really need to intervene or just let it ride.

BTW, are the levels you have now causing any issues you are concerned about, or are you just testing to know what's going on?

Thanks. I keep a pretty close eye on my levels and maybe Im getting sucked in to managing to the numbers. As a newbie its tough to interpret. What I do know is until mid-Dec or so my NO3 was always 5 or less, and phosphate was always around 0.1. So it’s the change over the past couple of months that made me wonder. But that might simply be the addition of fish and more food (?).

But to your point, I don’t think there‘s an issue. Just seeing the change and wondering how to manage it. But to your point I’ll keep an eye one the levels, but so far they’ve been fairly stable.

 

[DraggingTail]

Okay. My nitrates are running 15-20 and phosphate around 0.14 for my 120G reed tank. So I think it’s a bit high. I’d like to be 5-10 nitrate and low as possible for phosphates

I realize water changes won’t get me to my target as a long term solution. Rather not resort to chemical solutions. So what options do I have for long term reduction? Is it live rock in sump, somehow increase bacteria? Thanks in advance.

Leave it alone. More harm than good bouncing params around.

 

[Greg P]

But to your point, I don’t think there‘s an issue. Just seeing the change and wondering how to manage it. But to your point I’ll keep an eye one the levels, but so far they’ve been fairly stable.

OK, sounds good. No use worrying about parameters if you're not getting an algae issue.
If you were planning on adding some SPS, now would be a good time to start with some 'tester' frags as your params are pretty decent.

 

[Greg P]

Forgot to mention to ease your mind ...
Your current levels of NO3 and PO4 won't hurt your fish.
I wouldn't worry about Nitrates above 60. Some run tanks much higher, and reports show fish can tolerate over 80ppm, so your 20 is just ideal for a mature SPS tank.