Can't keep blasto's alive

[PedroYoung]

No problems with acans (lords, bowerbanki, hillea, echinata), euphyllia (torches, hammer, frogspawn), brains (trachy, Wilsoni, gonastrea). Parameters all good. Blasto's keep receeding until they perish. Keeping on the bottom of LED lit tank. Wondering if maybe water is too "clean"? Phosphates at 0.00, been trying to get them up by adding fish and part time skimming. Is there a blasto specific pest I don't know about. Nothing left behind when dipping. I am about to give up on them, I have tried 5 different beautiful varieties from 3 reputable vendors. Only other LPS showing any signs of stress are a few chalices where the color is washed out. Alk runs around 9.5, Ca about 450, temp 78, pH about 8.3. As I said, nitrates and phosphates are about nonexistent. I stopped running my phosban and carbon reactors to try and dirty it up a little, just wondering if anyone had any ideas.

 

[twilliard]

Lower ALK
what's your nitrates?
sounds like you have a ULNS tank.

 

[Birddog]

Subscribed... I feel your pain and would describe my tank similarly, although my nitrates are .25-.5, phosphorus at .04-.06, Alk @ 8ish, Calcium @ 450, Magnesium @ 1350 and everything in my tank has good to great color and my chalices grow like weeds.... but blasto's forget about it they receded until there's nothing left.

 

[Reef2Javi]

I found that my blastos love being inside my caves away from direct light

 

[PedroYoung]

Lower ALK
what's your nitrates?
sounds like you have a ULNS tank.

Nutrients low because of overdoing skimming and reactors (previous tank had hair algae and swore it wouldn't happen this time). Lower Alk to where? I am dosing 2 parts so can slow down the Alk dosing (slowly).

I found that my blastos love being inside my caves away from direct light

I tried this with one, but no light means I can't see it and couldn't let it go more than a week before putting it in low light area. Last 2 I have are in the least light I can give them while still seeing them.

 

[The Kahnasaur]

Agree with Twilliard. With no nutrients your Alk is high. Drop it to around 8 and see if things improve. It's very likely that this is the same issue effecting your chalices.

 

[PedroYoung]

Agree with Twilliard. With no nutrients your Alk is high. Drop it to around 8 and see if things improve. It's very likely that this is the same issue effecting your chalices.

Sounds reasonable, I am also attempting to raise the nutrient level via fish/ coral feeding. I was unaware of nutrient and Alk interaction. If I get phosphates up to 0.03 ppm or so would that change the sweet spot for Alk?

 

[rossco]

My blasto accepts mysis via direct feeding, you might give that a try if they aren't too far gone. They are at the front edge of a cave mounted vertically in direct light.

Quick iPhone pics:

 

[The Kahnasaur]

Sounds reasonable, I am also attempting to raise the nutrient level via fish/ coral feeding. I was unaware of nutrient and Alk interaction. If I get phosphates up to 0.03 ppm or so would that change the sweet spot for Alk?

I can't really comment on what level of phosphates would be ideal. I run a rather dirty tank due to feeding my NPS Suns and my Blastos and other LPS thrive. There's a bunch of more informed people that I've seen talk about the effects of 9+ Alk levels with ULNS in other posts which is what I'm grabbing my knowledge from.

On a side note, Blastos can behave rather oddly sometimes. I have one frag that will grow great for a year with new heads forming, and then suddenly recede quickly for a couple of days, while the mother colony and sister frags show no effects. It's done it twice now in the 4 years since its been fragged. Could easily be something other than the water but I've read about other people seeing odd behavior from Blastos so who knows.