High phosphates

[reeferdaddy]

Hey everyone thanks in advance for reading and giving your feedback and opinions !

I have newly transitioned to a reef tank from a 20+ year predator fish only tank that I inherited from my dad. Been about 6 months and I’m currently struggling to lower the phosphates (.45ppm)

I have live rock with coralline algae beginning to grow and my lps, sps, and softie corals appear to be growing well so far. I suspect that the phosphates are high dude to it being binded to 20 year old crushed shell substrate. I’ve been running phosban in a gfo reactor but I’ve hit a wall and it’s not lowering any more. What do you guys might be causing this and how would you go about lowering them ? If I end up changing my substrate will this wipe out my pod population ?

my other parameters are-
120 gallon
Nitrates 27.8
Phos .45
Alk 9.5
Sal .025
Temp 78 F
(From Hanna digital test kit )

 

[Reefahholic]

Hey everyone thanks in advance for reading and giving your feedback and opinions !

I have newly transitioned to a reef tank from a 20+ year predator fish only tank that I inherited from my dad. Been about 6 months and I’m currently struggling to lower the phosphates (.45ppm)

I have live rock with coralline algae beginning to grow and my lps, sps, and softie corals appear to be growing well so far. I suspect that the phosphates are high dude to it being binded to 20 year old crushed shell substrate. I’ve been running phosban in a gfo reactor but I’ve hit a wall and it’s not lowering any more. What do you guys might be causing this and how would you go about lowering them ? If I end up changing my substrate will this wipe out my pod population ?

my other parameters are-
120 gallon
Nitrates 27.8
Phos .45
Alk 9.5
Sal .025
Temp 78 F
(From Hanna digital test kit )

Tanks like these can leach for over a year depending how much was fed and how high the levels actually got. Looking at the numbers, it doesn’t seem like he kept insanely high levels of N or P. 0.45ppm PO4 is on the high end (that’s subjective), but not too crazy high. NO3 seems to be fine also, but maybe a little higher than some would like.

Typically if somebody overfed an extreme amount of food the nitrates and phosphates will both be higher and both leach for a long time.

You can keep trying to pull it out with absorption media like GFO or dose Lanthanum Chloride (I don’t recommend it because it’s a pollutant and dangerous). Water changes will also help speed up the process.

It really depends on what you’re trying to keep. LPS will be fine in those levels. Most Acro’s will do ok as long as it’s stable and not fluctuating all over the place.


If it were me, I’d just remove all that sand and if that didn’t take care of it, I’d probably change out the rock. It sucks to do that, but sometimes it can suck even more dealing with an unstable tank that is leaching for months. If the levels are stable and you’re ok with higher nutrients then keep it and just try to get it down over time if it’s bothering you.

Live rock can be like a instant tank if you want to go that direction I recommend KP Aquatics starter rock. Best of luck.