Polyp extention

[scampi1]

My system seems to be doing pretty well. I am just not getting good polyp extention on my sps. They are not dying, they just seem to not have good extention. I put frags of these in a buddies tank and they look hairy the polyps are so long. I have a 58 gallon with an ATI sunpower T-5 6 bulb. I have everything from leathers to LPS to SPS. Two things that seem to make no sense to me is that 1. I can not seen to get good polyp extention on SPS and for sum reason zoas do not last in my tanks and they are supposed to be the easiest things to keep. I Do weekly water changes (5-10 %) SG= 1.025, ph=8.1-8.2, temp 77.8, Most other levels 0ppm. Ca 420. Wsa vodka dosing. I am getting very frustrated. My light is only about 2 inches off water surface. Could this be too much for a 21" high tank. I am grabbing for anything, I am at a loss. Do not dose anything else and use brightwell salt. I started dosing BRS Ca and bicarb but was not helping. I use a hang on octopus skimmer and have sump with macro. Any thoughts

 

[scampi1]

bought new test kit today just to make sure. Come to find out my Calcium = 320 and dKh= 5-6. Both pretty low, never thought test would have gone bad. Could this lead to my issues. But my pH is still around 8.2. I know that this is not good but could it be responsible for my cyano or diatom outbreak.

 

[reefman]

very likely, yes. but hard to say for sure with limited info on your system.

 

[cowfish]

How old is the tank?
How old are the t-5 bulbs?
What do you use for water circulation?
Do you have a refugium with macroalgae?
How often and how much do you feed the tank?
Do you use carbon in a media reactor?


Your lighting is fine for your tank (depending on the bulbs). Lamps/bulbs typically undergo a spectrum shift with age which can result in increased nuissance algae growth.

A pH of 8.2 is great and would not have any negative impact on the tank. Definitely want to bring the calcium and alkalinity up and you should probably check your magnesium as well.

Cyano and diatoms are usually caused by excess nutrients in the water. Old bulbs and low flow can also contribute to their growth.

Lack of flow in the tank may also explain why you have poor polyp extension on your SPS. Many will tell you that you need 20-40X tank turnover per hour for SPS and the flow should be random, not laminar.

Leather corals don't mix well with SPS due to the resulting chemical warfare which may also be contributing to poor PE.