Water too clean for growth?

[uscgbeachbum]

I set my tank up about 8-9 months ago with the main goal of having a zoo/paly, shroom, ricordia, lps tank. I have 6 fish: kole tang, melanurus wrasse, tail spot blenny, and 3 clownfish. I feed about 4 times/week. I put my first zoo frag in the tank about 4 months ago. Unfortunately, I haven't had a single polyp of growth. I have 4 chalices, all of which are doing great (including growth rate). I've since amassed approximately 10-12 zoo frags, but I've lost a few to reasons unknown. I run 2xKessil A360WE's at about 25%. I have an RLSS R6i skimmer tuned to skim dry. I run a smaller section (12x15ish) of chaeto on a reverse photoperiod, but its nearly as dense as a cake. I just removed about a basketball size section (loose of course) and I still have about 2/3 of the chaeto.

So here's the thing...I know my intended corals want a "dirtier" tank. I change my water about every 6 weeks. Parameters are relatively consistent, but these are from last night.
Temp - 78 - 78.5 (Apex)
pH - 8.1 to 8.3 (Apex)
Ca - 460 (Salifert)
Alk - 8.3 dkh (Salifert)
Mg - 1380 (Salifert)
NO3 - 0 (Salifert)
NH4 - 0 (Salifert)
NO2 - 0 (Salifert)
PO4 - 0 (Hanna) (yes, that's 0 ppb)

My first thoughts were that my water was too clean. So about 3 weeks ago I increased the feeding to 3-4 times/day and reduced the skimmer to only 12 hrs at night (helps to stabilize the pH). As a last ditch effort I removed my bag of chemi-pure elite and bag of carbon (standard AquaClear bags that hold approx 1 cup of media) over the weekend. Literally no change in water chemistry from any of the changes. I'm at a loss here. My previous tank (broke it down in 2008) grew zoos like weeds (55 gal tank with 2x175 halides).

Any thoughts?

 

[Tim Cannon]

I have never used kessils but the % your running seems low. Idk. On my standard size 180 I run 3 ai Vegas colors, 25% white, blues at 55% and red and greens at 30%. At about 9 inches above the water. In my experience with my zoas they like a little phosphate and nitrate. My tank runs between 4-6 ppm on nitrate and I don't test for phosphate that often or run any media for it. When every thing was testing at 0% I was losing the few sps frags I had. What kind of flow do you have?

 

[uscgbeachbum]

I have never used kessils but the % your running seems low. Idk. On my standard size 180 I run 3 ai Vegas colors, 25% white, blues at 55% and red and greens at 30%. At about 9 inches above the water. In my experience with my zoas they like a little phosphate and nitrate. My tank runs between 4-6 ppm on nitrate and I don't test for phosphate that often or run any media for it. When every thing was testing at 0% I was losing the few sps frags I had. What kind of flow do you have?

Thank you, Tim. I'll have to look into increasing the intensity. I've got relatively low flow from my DT to sump (est. 200 gph), but in the DT I have 2xJebao WP25s. One is set to a long wave and the other set to a short wave.

 

[reefwars]

Lighting would be my guess as well as for the slow growth.


If your growing cheato then I wouldn't necessarily say that your water is too clean , I have zero detectable nitrates in a heavily carbon dosed system that runs gfo to keep po4 aggressively around the zero mark and I have a couple thousand pieces of about 150+ types and growing incredibly fast and colorful. We rarely lose a polyp to anything and haven't for years, some pieces I have I have had up to 6 yrs and still going strong producing polyps today.

Flow is a big thing , I have a flow rate of over 90x but I also have no sand or loose things to blow around.

I also skim pretty heavily too and Turnover rate thru our sump is about 6x

I rarely feed corals anymore

 

[reefwars]

With all that said though there is no harm in feeding your polyps if you feel like they aren't getting enough

 

[uscgbeachbum]

Lighting would be my guess as well as for the slow growth.


If your growing cheato then I wouldn't necessarily say that your water is too clean , I have zero detectable nitrates in a heavily carbon dosed system that runs gfo to keep po4 aggressively around the zero mark and I have a couple thousand pieces of about 150+ types and growing incredibly fast and colorful. We rarely lose a polyp to anything and haven't for years, some pieces I have I have had up to 6 yrs and still going strong producing polyps today.

Flow is a big thing , I have a flow rate of over 90x but I also have no sand or loose things to blow around.

I also skim pretty heavily too and Turnover rate thru our sump is about 6x

I rarely feed corals anymore

Interesting. I'll slowly increase the Kessil strength and also try to tweak the Jebaos. I've been target feeding Reef Chili about 3-4x per week as well. Currently looking into Vitamin C dosing as well.

 

[Tim Cannon]

Turn the flow up for sure. I have 4 mp40's on reef crest turned almost all the way up and a dart gold for my return. I also use reef chili 2-3 times a week broadcast fed and also use reef energy a+b for my vitamins.

 

[zn00py]

zoas are tricky for me to .I have seen them grow in unkept tanks and tanks which have great parameters.I myself have had problems with them growing in my tank.I would say out of about 10 different zoa frags only 4 of them have been fully opened .I've moved on to lps corals like acans and favia's