Proper way to reduce nitrates but minimize stress to a mixed tank

[Greg B.]

Looking for some help on reducing nitrates. The past few weeks I've noticed my nitrates have continued to increase slowly week to week. I have 50.gals total between sump and DT. Nitrates are 30ppm. My filtration is into the sump, 10 micron felt filter socks, into a refugium and I still run my HOB filter(for some reason). Socks and cartridge get cleaned every 2 days. Up until 2 months ago I've done 10 gal waterchanges every 2 weeks. My refugium had a huge wad of chaeto that I've noticed the past 4 weeks has broken up and reduced in size. I'm curious how much of a water change do I need to do to reduce my nitrates? Is it better to do smaller water changes every few days or a large water change? I do have alot of algae growing on the back glass. My thought was if I let it grow it will eat the nitrates. But I haven't seen that to be benificial. Any help or thoughts would be great. TIA

 

[VinnyBoy]

I’d be concerned the chaeto is dying but nutrients are increasing. Are your phosphates in check as well?

But to lower nitrates effectively water changes do great yes. The primary source though is going to be how much you feed, so you could also cut back on that to help.

 

[Reefering1]

Nitrate increasing is likely because chaeto is dying. What are your phosphates? Iron?

 

[Greg B.]

 

[Greg B.]

April 4th is when I added the chaeto. The24th I had 3 readings using a hanna meter of 0ppm. I pulled half the chaeto out. And then I noticed the climb and I can't get it down. But as for the chaeto I am not sure why it's breaking up. I put in 2 large wads equating to about a 10x10 and now I am down to maybe 3x3. Alk is 11.1, cal 435, mg is 1350, phosphate is .06, salinity 1.026, temp 77.5, ph 8.36. I dose all for reef 10ml per day.

 

[Greg B.]

Nitrate increasing is likely because chaeto is dying. What are your phosphates? Iron?

I don't check iron. Is this something I should start checking? What does high/low iron do?

 

[Malum Argenteum]

Short term nitrate reduction: water changes.
Long term nitrate control, with other additional benefits: skimmer.
Long term serious nitrate control: skimmer + sulfur denitrator.

 

[Reefering1]

It's also possible that you added more chaeto than you had nutrients for, so it started dying- increasing nutrients. Ime, It's a balancing act with chaeto. Sometimes it grows very well stripping nutrients, other times it's dying back and releasing those nutrients. Now a days I just feed alot, dose vodka to control nutrients and let the chaeto act as a nutrient buffer to prevent bottoming out.

Pics and details of tank..(?)

 

[UMALUM]

I've always been a fan of daily 10% changes till the volume is flipped once. Then reload and see where your at.

 

[metro6775]

Looking at your numbers I don't understand why your chaeto is dying. I have been working down a severely high nitrate count. I'm talking it was 75+ flashing on Hanna. I added chaeto and performed 5 % water changes almost every week since 3-18 and my nitrates are down to 40 last test a week ago. I dose Brightwells Chaetogro and I now have a sump full of chaeto. I dose half the recommendation. I also dose phosphate because I can't keep it above zero.

 

[Dan_P]

Looking for some help on reducing nitrates. The past few weeks I've noticed my nitrates have continued to increase slowly week to week. I have 50.gals total between sump and DT. Nitrates are 30ppm. My filtration is into the sump, 10 micron felt filter socks, into a refugium and I still run my HOB filter(for some reason). Socks and cartridge get cleaned every 2 days. Up until 2 months ago I've done 10 gal waterchanges every 2 weeks. My refugium had a huge wad of chaeto that I've noticed the past 4 weeks has broken up and reduced in size. I'm curious how much of a water change do I need to do to reduce my nitrates? Is it better to do smaller water changes every few days or a large water change? I do have alot of algae growing on the back glass. My thought was if I let it grow it will eat the nitrates. But I haven't seen that to be benificial. Any help or thoughts would be great. TIA

Sounds like my system some years ago. Some thoughts.

If the Cheato is not growing, it is not removing much if any nitrate. My Ulva stopped growing because of depleted trace elements and came back strong after dosing Cheatogro (1/7 the recommended dose was enough for my situation).

You can grow algae anywhere you want to remove nitrate, but you must harvest it to remove the nitrogen. Not harvesting it means it crowds itself and growth slows and stops. So, no sitting back and watching the weeds grow to reduce nitrate

Changing water removes nitrates. If you change 20% of the water, the nitrate level will drop by 0.8 X

 

[Greg B.]

Sounds like my system some years ago. Some thoughts.

If the Cheato is not growing, it is not removing much if any nitrate. My Ulva stopped growing because of depleted trace elements and came back strong after dosing Cheatogro (1/7 the recommended dose was enough for my situation).

You can grow algae anywhere you want to remove nitrate, but you must harvest it to remove the nitrogen. Not harvesting it means it crowds itself and growth slows and stops. So, no sitting back and watching the weeds grow to reduce nitrate

Changing water removes nitrates. If you change 20% of the water, the nitrate level will drop by 0.8 X

So in order to get the nitrates out I'd have to remove the growing algae on the back wall?

 

[Dan_P]

So in order to get the nitrates out I'd have to remove the growing algae on the back wall?

Yes. Removal is important.