Struggling to keep nutrients am I understocked?

NoobishReefer22 · Jul 9, 2026

hello all I wanted to get your opinion I have been struggling with keeping nutrients in my tank. I currently have a 80 gallon shallow reef here is my stocking list and filtration current nutrients sitting at 0.03 phosphate and 4ppm nitrate this is when aggressively dosing nitrate and phosphate everyday for the past week.

Stock list:

Desjardini Sailfin - 4 inches
Flasher wrasse - 3 inches
Melanarus wrasse - 3 inches
Yellow Coris wrasse - 2 inches
Hawkfish - 3 inches
3x Green Chromis
Springeri Damsel - 1 inch

9 fish in total.

Filtration:
4 inch filter sock
Fleece Roller
biospheres

Saltyreef · Jul 9, 2026

Sounds like you need to remove the sock or the roller...feed more. Forego water changes for a bit....

EnterName · Jul 9, 2026

Natural coral reef nutrient levels are often below the detection limit of hobby test kits. While natural levels might not be optimal in a tank (alkalinity is another example for this), your corals won't starve. I had 0ppm nitrate for years without issues. Nitrate has to be reduced back to ammonia before corals can assimilate the nitrogen, which means they prefer ammonia and only will consume nitrate if nothing else is available. That's why you want to dose ammonia instead of nitrate if you aren't doing that already:

https://www.reef2reef.com/threads/diy-ammonia-dosing-for-low-nitrate-systems.987087/
I personally wouldn't reduce the filtration or increase feeding as it will just cause the accumulation of detritus and increase not only nitrate and phosphate, but also dissolved organics. If those were a limiting factor you wouldn't need to aggressively dose nitrate and phosphate.
I don't think there is anything bad about dosing nutrients instead of overfeeding. It keeps the water clean and is much easier to control if for some reason nutrient levels were to rise at some point. Removing detritus from overfeeding on the other hand is very tedious.
It's possible that your corals don't get enough particulate food though. If you aren't doing this already you might want to feed them with coral food

slingfox · Jul 9, 2026

Need more details about your tank for people to properly advise. Specifically, how long has the tank been running and what is the corlamload. Pictures of the display tank would also be useful.

Your parameters seem fine as is. What and how much are you dosing for Nitrate and Phosphate? How much and how often do you feed your fish? What are you running both fleece socks and a filter roller? Do you run a protein skimmer or refugium?

whalewhalewhale · Jul 9, 2026

My former heavily stocked SPS tank was a constant battle to keep nutrients up. I tried stocking more fish and it barely made a dent. Fed 3+ times a day and nope.

Eventually I just put ammonium chloride and neo-phos on a doser and forgot about it. I gauged nutrient levels with coloration rather than chasing numbers. Acros start to look pale? Maybe up the dosing.

Remember, that corals can uptake ammonia directly... which can lead to nitrate appearing lower, but not being an issue at all.

Mr. Mojo Rising · Jul 9, 2026

How do your corals look? Thats the most important thing.

NoobishReefer22 · Jul 9, 2026

slingfox said:
Need more details about your tank for people to properly advise. Specifically, how long has the tank been running and what is the corlamload. Pictures of the display tank would also be useful.

Your parameters seem fine as is. What and how much are you dosing for Nitrate and Phosphate? How much and how often do you feed your fish? What are you running both fleece socks and a filter roller? Do you run a protein skimmer or refugium?

Tank has been up for 1 year but I was using live rock from the same tank that I took down for 3 months as I moved. The live rock was cooking in a brute bin the whole time. Previously the tank was up 2 years before I moved. My parameters are fine when I consistently dose but if I stop the it bottoms out and causes dino's.

Overall corals are doing okay not good and not too bad some slow growth. It is an AIO only filtration is 1 filter sock and 1 fleece roller its a Innovative Marine fleece roller the automatic one.