zoo help

[viet-tin]

i had some very nice zoo colonies and recently their numbers have been falling. I dont see any nudis or sundials. I did a fw dip and the only things i found were limpets a few small brown olive snails asterina and brittle stars. It started from one of my smaller colonies and now spread over into my large colony. I also recently change my lighting from 2x250w mh down to 2x150w hqi and have also noticed a huge algea cyano bloom and thats beggining to smother my zoos as well. Anyone know whats killing my zoos?

 

[network13]

did you increse the light cycle? Are the lights new or used? Used lights will shift spectrum and grow algae.

 

[oceana]

very hard to tell without seeing them but algea can and does kill zoanthus. try adding some more flow to the tank. or moving them to a place in which they get more flow.
what are your water reading? ALL of them

 

[viet-tin]

The 150w hqi are brand new so im thinking this is the cause of the algea bloom. Its not out of control and is not spreading like crazy anymore. I have plenty of flow in the tank. Im running a tunze stream 6080 along with 2 seio 820 and a mag12 for my return. Tank is a 100 gal with 200lbs of rock 55 gal sump/fuge. running a euro reef cs8-1 skimmer.
water params
NH4=0
NO2=0
N03=0
PO4=0
ph=8.3
Ca=400-450
Alk=3meq/l
Dkh=8