Cannot control nitrate and phosphates.

[zchauvin]

Hi guys, I have been fighting phosphates and nitrates to no avail. I’m running HC GFO at 120 grams ( roughly 120g total water volume ). Skimmer is a BK 160, wet skimming. Also carbon dosing nopox 14.4ml per day. Nitrates after 14 days at around 30 ppm, and phosphates will get down to around .10 over a day or two then straight back up. Doing 40g water changes helps for about 3 days. I could possibly add a refugium but was under impression GFO and Carbon dosing should’ve been sufficient. Should I double the amount of GFO in reactor?

 

[fish_collector]

I have high nitrate and phosphate in my SPS tank, they're floating at 30 and 0.7. I've dabbled in reducing them but it's not as easy as it sounds, perhaps because the calcium carbonate rocks retain so much of it. I've not noticed too much difference in the health of my acroporas since it's creeped up, and I certainly have no nuisance algae either, so I've been letting it go . I'd like to get it back down to levels that are more widely accepted as normal, but in the absence of a good strategy I'm ignoring it for now.

 

[EnterName]

Maybe the export isn't the issue but the import. Rinsing frozen food might make a small difference, feeding less and more targeted is another option. If the tank is overstocked you will constantly have to find a way to keep nutrient levels down.

I don't know how fast GFO can drain phosphate in comparison to precipitated phosphate redissolving. But if GFO is faster it's also possible you just see your rocks and substrate leeching phosphate back once you remove the GFO. This keeps on going for quite a while so in that case you just need patience.

 

[exnisstech]

Today is test day. Nothing's complaining in my tank.

 

[zchauvin]

Maybe the export isn't the issue but the import. Rinsing frozen food might make a small difference, feeding less and more targeted is another option. If the tank is overstocked you will constantly have to find a way to keep nutrient levels down.

I don't know how fast GFO can drain phosphate in comparison to precipitated phosphate redissolving. But if GFO is faster it's also possible you just see your rocks and substrate leeching phosphate back once you remove the GFO. This keeps on going for quite a while so in that case you just need patience.

I do have what I consider to be a lot of fish, and I do feed heavy. My concern is that new additions (coral) would be shocked if they are coming from a typical lower nutrient system.

 

[EnterName]

Maybe the export isn't the issue but the import. Rinsing frozen food might make a small difference, feeding less and more targeted is another option. If the tank is overstocked you will constantly have to find a way to keep nutrient levels down.

I don't know how fast GFO can drain phosphate in comparison to precipitated phosphate redissolving. But if GFO is faster it's also possible you just see your rocks and substrate leeching phosphate back once you remove the GFO. This keeps on going for quite a while so in that case you just need patience.

I do have what I consider to be a lot of fish, and I do feed heavy. My concern is that new additions (coral) would be shocked if they are coming from a typical lower nutrient system.

Corals don't really like sudden phosphate spikes so that might actually cause issues after a few days. That's also the reason why I sometimes recommend to reduce phosphate even if levels are within Randy's target ranges which are definitely safe and allow for healthy corals. The sudden change is what some more delicate corals don't seem to like. It doesn't have to be fatal, but some respond with tissue necrosis.

 

[56longroof]

My tank runs a 20 nitrate and .1-.3 phosphate consistently. Never any issues with adding corals. I dont even acclimate them.

 

[davidm777]

Hello. I am not expert but I understand the aquarium to be a system. Your water flow and your lighting will play a big role nutrientes as well as your bioload and your routine.
Personally I would recommend using GFO and carbon dosing (NoPox) as a temporary tool as you get your system balanced and work on a long term routine.
Could you add a picture of your aquarium and your sump as well as lighting schedule and feeding routine? This will help to troubleshoot on the specific needs of your system.

 

[Mortaliton]

I know it was already mentioned previously. In my experience I did a fish only tank for a year before I decided to track all the elements and stuff.

Phosphate was never on my radar during fish only. Once I started testing and realized the tanks phosphates were way out of control I installed a GFO reactor. I have a massive labyrinth of rock to form a base coral structure when I started testing getting them.

From what I can tell due to sitting in a phosphate bath for a year they absorbed a lot. I burnt through a reactors worth of GFO every week or less for 3 months. Now I can run a single reactor for over a month before I need to replace.

I only had a hunch and a lot did point to leaching rocks. If this is something that is a possibility in your situation. Fill a bucket with clean RODI water and put a rock in there to sit for a couple days. Test the water and if you detect phosphates then the rocks are leeching.

There are ways to clean the rocks. It does involve removing them if I recall. But someone else with more experience will have to chime in with the correct info.