Phosphates in SPS tank

haze152

New member
I have a 6 month old 75 gallon SPS dominate tank 30 gallon sump. My phosphates are .36 hanna test and I can't seem to get them Down I have tried a couple different brands of GFO both in bag and reactor. All of the corals seem to look fine in fact a couple of browned out acros are coloring up. Does anyone have any other suggestions to lower them. No sand just enough crushed coral to cover bottom water changes ever 2 weeks 10% then 20%. Tank was started with live rock mixed.

PH 8.4
Alk 9
Cal 450
Everything else 0
Water temp 78-80
2x250 MH 6 hours
4 attintic 9 hours
Coral life 120 in sump skimmate is dark green.
Fish 1 clown 2 green crhomis 1 sailfin tang 1 yellow eye. I feed fish half a cube frozen once a day not low end food.
Coral zoa's frogspawn torch hammer Duncan 2 different birds nest 8 different acros 1 acan.
 
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Are you using water close after when your feeding your fish? Try to take readings from different areas of your tank and sump.

Did you say the Red Sea low end PO4 was 0?? I have both Hanna and Red Sea PO4 and they commonly produce different results, with Red Sea usually being lower than Hanna. My Hanna Phosphorus checker can read 75ppb P (=0.23ppm PO4) and then 30 min later it will read 22ppb P (=0.067ppm PO4). So if you have enough reagent packets(if using the Hanna PO4 checker), make at least 3 readings in different areas and at different times.

If there is no change:

You should make sure your PO4 reactor is working correctly. Is the feed pump clogged or is the GFO clogged with detritus? Just make sure that's all clean and filter the water before it enters the reactor.

Also do you have enough flow in the DT to not allow for dead spots where waste can settle. Make sure it all gets to the sump and the skimmer.

I use a filter sock and foam block to capture all the large waste and algae and clean them every week and rotate a second pair while I wash them.

But the main advice I can give you is to change your water regularly.
 
I use a filter sock I change ever 2 days. Flow in dt is 3 PH totaling 3000 GPH with mag 9 return I did 2 test yesterday dt .35 sump water after reactor .15. I am going to go a 25 gallon water change when I get home. In theory that should drop it to .23. I was then going to run phosgaurd for a couple days to drop it fast then maintain with GFO. Any input on this would be great.
 
You can try PHOSFree. Mix it 5-10ml per gallon and drop dosing in filter sock. Despite some negative reviews I've never had any problem with it and I have all type of corals and fish. It dropped my phosphate from 1ppm to 0 in about a week. One bottle will last you lifetime. The only downside you have to change filter sock more often.
 
What is the phosphate of your new saltwater? I recently ran into my IO being .10 which didn't help matters for doing larger water changes.
 
I use a filter sock I change ever 2 days. Flow in dt is 3 PH totaling 3000 GPH with mag 9 return I did 2 test yesterday dt .35 sump water after reactor .15. I am going to go a 25 gallon water change when I get home. In theory that should drop it to .23. I was then going to run phosgaurd for a couple days to drop it fast then maintain with GFO. Any input on this would be great.


GFO works best with a reactor and is more effective than phosguard....get a reactor and use a high capacity GFO (such as the 1 at Bulkreefsupply), use 1 cup per 100 gallons only and change it weekly and along with large weekly water changes you should be fine in no time. Consider researching Carbon dosing also, albeit that helps trates better than phates....
 
I am running High GFO now in rector. I did a 25% water change this morning media is 3 days old I tested level tonight and its down to .10
 
I have thought alot about vodka dosing and have done alot of research I have seen alot of pros and cons.

I personally would not consider vodka dosing with your current skimmer. While I run zeovit and have great results with the system (whole different topic), I wouldn't consider and carbon dosing without a more powerful skimmer. A better skimmer may help if the phosphate is being driven up by dissolved organics. Just my .02, something to think about.
 
I'm in the same boat was at 3.9 I got new box of regents and now down to 1.0 I think a better skimmer would help also
 
On vinegar dosing, I've been adding a teaspoon of Mrs Wages Pickling lime with about 20ml of vinegar for each gallon of RO/DI water I add to my ATO. As someone mentioned, I would recommend the best skimmer you can afford, as the carbon dosing causes a significantly higher volume of skimmate in my system. Due to a heavy bioload, I run my skimmer on the wet side. There is a great thread started by TMZ on carbon dosing. It takes a while to read through, but recommended reading prior to starting your dosing program.

IME, the carbon dosing doesn't do much in reducing phosphate levels, but has dropped my Nitrate levels to unreadable levels with the Red Sea test kit. I use high capacity GFO in a Little Fishes 150 reactor to keep my phosphate levels around .06. I change out the GFO every 2-3 weeks. My SPS and Zoas seem very happy. I feed my fish 3x daily with an autofeeder. The fish poop is the only thing that is fed to the corals/zoas. PE and coloration are great. Hope this helps.
 
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