Tony, I am pretty sure I have relatively high phosphates...I have cyano and numerous pest algaes trying to poke their noses in where the fish can't reach them but my corals grow like mad,...it would take a lot to convince me your sps problems are because of phosphates

I would also love to hear others' perspective on this. I had a similar problem with growth and survivability with SPS in my previous tanks, and now in my current tank my SPS are thriving and growing despite the fact that as far as I know, I'm not doing anything any differently than in my previous tanks. Still using GFO and carbon, same circulation pattern, exactly same lighting, same water source, etc. So I'm most interested too, Delphinus. Sorry about directing the thread away from the original intent, by the way.

I run Rowaphos(gfo) in a reactor
Cheato in the fuge
never have tested for phosphate

Phosphate test kits are a waste of money IMO.

My experience is almost identical to yours, Tony....right down to using the colorimetre.

To Marie's point... If you measured for phosphate, I bet you would be surprised. I started testing phosphate and trying to reduce phosphate because I grow a lot of algae and cyano and I'm always told "to get rid of cyano, you have to reduce nitrate and phosphate".

So here's the rub: I've never been able to measure any significant nitrate or phosphate in my system using the best measuring equipment that can be reasonably purchased. So I'm told "that's because all the algae and cyano are using it up before you can measure it".

I run RowaPhos in a TLF and change it out about monthly. I have never been able to determine if that is an adequate schedule or not.

I've been VSV (vodka, sugar, vinegar) dosing for almost two months now and in spite of increasing dosage nothing significant has happened. (I still measure almost zero nitrate and phosphate). Well...my chaeto has basically died so I guess something has happened....but I still have a lot of cyano issues.

If that's the case then wouldn't the algae and cyano also be removing it before it can affect coral growth and therefore be a non issue?

From my understanding, all living organisms uses phosphates to some degree and it follows any food you add to the system will have phosphates bound up in it (whether it's listed on the label or not).
The more animals and plants you have living and growing in your system, the more phosphates get taken out of the water column. Problems arise when there is too much phosphate getting bound up in the coral skeleton that's when it starts to affect tissue growth

....some phosphate good, too much very, very bad :lol:

My 90g has been running for 2 years and has a pretty large bio-load. I have never had noticeable PO4 or NO3 readings on either Salifert or Elos kits. SPS grows quite well in this tank and very seldom do I have issue with algae growth.
In the 225g tank however, SPS doesn't do crap. A few pieces do ok and others not so good. I am always having algae issues as well. P04 readings in this tank are undetectable and N03 are about 10 to 15.
Both tanks get 10% water changes bi-weekly, both have refugiums with DSB and large amounts of macro-algae. I have tried Tailored Aquatics Nitrate and Phosphate Destroyer; vodka dosing; and larger water changes on the 225g: with no positive results. SPS continue to struggle and algae growth has not been reduced.
The only difference I can see between the 2 tanks is the rock I used when setting up. The 90g was all live rock, while in the 225g I used a lot of BRS Eco-Rock. Perhaps there is a lot of phosphates bound up in this rock and continues to leach out. :noidea:

[quote]The only algae complaint I had with my tank was the film algae on the glass that would appear more frequent than I would like. I recently discovered that this was mostly due to the low southern sun blasting into my living room in the afternoon when I wasn't home and hitting the tank dead on! I've fixed that by closing the blinds[quote]

I know the feeling, I know when the wife left the blinds open all day as I get a green mist on my glass. I asked her to leave the blinds closed and she told me to get rid of the tank. So we compromised and I clean my glass every day.:biggrin:

I've never been able to get a phosphate reading, even when I had a patch or two of cyano, when I went through my Bryopsis phase, etc. But my tank does go through an awful lot of calcium, more than I think should be needed for my coralline algae and single open brain coral :lol: I feed only drained mysis so the phosphate input is probably not too high, but I suspect it's being bound by the calcium before anybody else gets to it.

I've never tried to get a reading, it's not something I've ever been too concerned with. I assume using my zeovit reactor has an effect, as I have no algae at all. I stopped using the reactor for a while, and grew a few different types of algae, from cyano to wafer. Within weeks of using the reactor, the algae is almost gone. Good enough for me.