type of Algae? picture attached

[Sammik]

hi all,

tank is generally going well but seem to have some algae that i am struggling to shift (please find the picture attached) it is all around the rocks, not slimey, just green and brown. PH is around 0.25, Nitrates about 10-15, ammonia 0, salt 1.025, calcium around 440.

lights are LED 200w blue and white and blue are on for about 10 hours a day with white on for around 6.

we have a relatively new sump with cheato (still small) and live rock with some ceramic balls too (not sure if this is possibly housing the nitrate causing the problem????) we have a protein skimmer on all the time.

at the moment fish are fed about 3 times a week with spectrum and corals/ nem's fed once a week with prawn's/ reef roids/ lobster eggs depending on coral and take out around 15-20% water per week. Replace with RO/DI water and salt (RO unit has been used for the past 2 months but before that was tap water - another possible reason??)

i guess i have a few questions if anyone can help:


i heard there is possibly an additive to help eliminate algae of this kind but it is poisonous and too much would kill pretty much everything. has anyone got any experience using this?

how long should i give the cheato and refugium to hopefully remove the Nitrates?

should i lower the time which the lights are on for?

should I do a big water change?

i dont use any carbon and no vodka dosing, is this worth looking into?

thanks!
Sam

[bertoni]

I'd give the refugium at least a few weeks, or more, to begin helping. The phosphate and nitrate levels are both high (assuming PH is phosphate), so carbon dosing might be worth considering. I suspect the nutrients are coming from the food, so I'm skeptical that a water change is going to do much over the long haul. You might want to check how much you're feeding.

[Sammik]

thanks Bertoni - will look into this!

[bertoni]

You're welcome! Good luck!