GFO, LPS, Snails, P and PO4 - Low nutrient problems??

[Zalick]

Background:
I've never had an algae problem with any tank I've run over the last 20 years. Generally I've run a 10g, 20 long and 55g hex. When I upgraded to a 300g, I decided to run GFO in order to keep phosphates in check. I've been battling GHA pretty for the last couple years.

My parameters are as follows:

Temp = 79-80
Salinity = 33.5 / 1.025
Ph = 7.9 (night) - 8.1 (midday)

Alk = 7.5 - Hanna
Ca = 457 - Hanna
Mg = 1320 - Salifert
Nitrate = 0 - Salifert
Phosphate = 0 - Hanna ULR

Lights = half Kessil a360w and half Mitras LX7

Fish totally fine (10 year old clownfish happy as ever)
Shrimp totally fine

The issues:
1. My hammers have been multiplying pretty consistently but minimal polyp extension.
2. New two head duncan was open for maybe the first week, now its been closed for at least a week. It is trying to grow a couple more heads.
3. My banded trochus and zebra turbos all die within a month or so. But my fighting conch is going on strong at year 2.
4. My GSP won't grow at all (I swore to never have this stuff again, but wanted to see if they would even grow in this tank and I have them very isolated to control the spread)

Since I have GHA growing pretty quickly, I must have some nitrates and phosphates in the water but my hanna tests always show 0. I've tested with Salifert and Red Sea and they also show 0 for both.

Are the low nutrients the likely cause of my poor LPS extension and/or snail deaths? The GFO?

I can't for the life of my figure this issue out. Its driving me nuts.

In my prior tanks, I always used compact fluorescent, T5 VHO or MH lights. The 300g is the first time I've used LEDs and consequently, the only time I've had trouble with corals or anything...

Any thoughts?

 

[murphreef]

What are you using for your salt water?

I always find one of the main causes of algae issues to be old RO/DI filters or just poor water when making your salt.

Anytime I notice any algae growth I change my filters do a fresh WC and usually issues subside.

 

[Zalick]

I have a spectrapure maxcap 180gpd 2:1
I have a booster pump with the pressure set at 80. I also have a big blue carbon filter before everything.

Change prefilter on pressure drop. Change carbon every 6ml or if breakthrough. Low TDS water (20) to begin with and 0 on output.

I was using Kent reef mix. Now using regular IO.

Sent using Tapatalk

 

[outssider]

Are the low nutrients the likely cause of my poor LPS extension and/or snail deaths? The GFO?

Yes.....star polyps too !!.....dirty things up a bit and that problem will be gone....unfortunately, the hair algae will go nuts...your kinda stuck here...have you tried fluconazole, if not, do some reaserch on it....

 

[Zalick]

Yes.....star polyps too !!.....dirty things up a bit and that problem will be gone....unfortunately, the hair algae will go nuts...your kinda stuck here...have you tried fluconazole, if not, do some reaserch on it....

I was shocked the GSP wasn't growing. The one and only time I had GSP, my first tank 20+ years ago, it absolutely went nuts. I was using tap water, filtered through a brita, and power compact lights. Grew a clam from 1" to 4". I had no idea what I was doing and everything worked....

My wife is a vet and wrote me a rx for a full dose of fluconazole. Have it loaded and ready to go, but was hoping I could beat the GHA with clean water...

I took the GFO offline today. Will try and raise the phosphates and nitrates up to detectable levels.