What do you have on the back glass? is that hair algae?

I had a little hair algae before and found out the problem with testing for phostphate/nitrates with a tank full of hair algae is that they would absorb it all and then your tests would be all skewed. I had tests showing 0 ph and 0 nitrates but having hair algae in the tank would mean that the tests are giving a false negative. Having that much hair algae in your tank and having the tests still showing phosphates would mean that there is too much even for the hair algae to feed on. I was over feeding my tank and probably still am but I have added gfo and algae grazers to prevent another outbreak in my new tank.

That's so weird, my Hanna tester has been fairly accurate thus far, I use salifert, redsea, and elos. Usually all within 20 ppm difference. Which mag test kit did you get from brs? I only have salifert and red sea to test mag but never does it hit that kind of numbers... See what ever is cheaper, either send a water sample to myka or if it's cheaper and faster you can send it to me in bc and I'll test it for you too. My wife does a lot of the testing for me which I found to be better, she is a lot more careful and accurate than me. :redface: are you still dosing probiotic by chance? How long ago did you start that system, was it prior to the crash, maybe the answer to your current issues is related to probiotic system. Did you test the freshly made salt water and see what kind of results it gives you and maybe use it to reference the results from your tank water. Keep in there bud. It will work itself out.

Doch, Have you tried carbon dosing? I think it would get rid of your nutrient issue.

+1 & make sure to inoculate with a bacteria source. Also maybe get the biggest mixing reservoir you can find in relation to your total display volume & try a huge water change by adding a bit cooler water closer to the bottom while siphoning the warmer water from close to the surface.

If you have algae growing in the tank - especially copious amounts - it will suck all the phosphate and nitrate out of the water so your kit can't detect it. If there is algae there is phosphate, can't argue that. Plus, when you added that frag tank on the algae bloomed in there like no tomorrow pointing to nutrient issues. Phosphate is a coral killer. Algae can help in a way by sucking the nutrients out o the water, but many algae also release toxins used as an offense tactic to help themselves spread.

The rocks are poorly designed for flow, and look like they collect a lot of detritus. I also notice that many of the rocks are from dry base rock, which I really don't like. I've seen algae blooms like this when using base rock so many times. Many base rocks will leech phosphate because they were alive at one point. Other base rocks are too dense to colonize anaerobic bacteria so have no ability to process nitrate.

It does not appear to be a safe place for SPS corals. I would suggest you at least use a siphon to suck out algae as you scrape it off the back glass (and anywhere else). If you're not using a filter sock, I would suggest you put one on the tank at least while you are getting the algae under control.

I have not tried Carbon Dosing. I think that I will. I do have some questions about it though. I recently added GFO, and more importantly added the right amount as per the BRS reef calculator. My PO4 went from 0.20 on the hanna, down to 0.10 with too little GFO, and down to 0.00 with the right amount. At each step, I could see a distinct decrease in the growth of the hair algae. I still have issues with blooms, but all levels are undetectable, adn the growth has slowed significantly. Would I be OK to start Vodka dosing right now? Would I be smarter to take the hit on sleep, and properly set up my Zeo system? Can you dose vodka and run zeo at the same time? What about N/P pellets? I have them, and a reactor, but for some reason it takes a lot of work for me to get proper tumbling out of them... they make me ANGRY!! lol.

I don't notice much in the way of detritus at all actually. I did for a while because I was waiting for a VERY long time for my 6105's to show up, and then had a power supply issue with my wavebox, but now that the proper flow is in there, I see no detritus. You may be on to something with the dry base rock... I can't confirm or deny. That is however one of the few things that changed from the old tank to this one.

What does this mean? Would dosing zeo bak suffice?

I'll be posting all new entries in regards to this under my tank journal. Should you like to follow, feel free.