Input...need input...

Junkie · May 14, 2010

Alright I have a couple of questions. I'm getting high phosphate readings with my salifert test. It expired in December last year. Do you think it is still fairly accurate? I know I'm having issues due to more film algae on the glass than normal. I have a 30 gallon tank (no sump) that I change 5 gallons a week on with ro/di and I'm using tropic marin pro reef salt. For fish I have a 2 1/2'' foxface, an ocellaris clown, coral beauty, flame hawk, and a chalk basselet. The tank has been up and running for three years, i'm running a crappy prizm skimmer and I have a small penguin (i think) biowheel HOB filter that I run carbon and polyfilter in which I change every week. I feed flake food 1-2 times daily, and feed my lps rinsed pe mysis once a week. In the three years I have never cleaned the sand bed that is aprox. 2'' deep. I'm thinking that this might be the source of the problem. When should one change out the sand bed? Am I due? If so how would one go about it? I'm worried by syphoning out the sand I could release masive amounts of amonia and detrius.
Here are my last test results if it makes any difference
calcium: 455
dkh: 7.7
phosphate: 0.10
mg: 1500
sg: 1.025
no2: n/a
no3: n/a
I know I should have tests for the last two, but I never replaced them because until recently I have never had a problem. Any insight on this problem would be greatly appreciated. Oh yeah I forgot, I just got a media reactor and have been running carbon through it for about a week now. Any suggestions are welcomed as well in regards of husbandry. Thanks so much.

Troylee · May 14, 2010

Start running rawaphos in a reactor or dosing vodka.... Also lose the flake food it has more po4 than most foods out there...

Paul_N · May 14, 2010

+1 on the GFO and the flake food. If you still want dry food move to a pellet like Spectrum. I feed it daily along with a different frozen. How big is your tank? You shouldn't have to change out the sand. Maybe add more over time. My sand bed is about 5-6" and 6 years old.

dakotasreef · May 14, 2010

I have heard that older sandbeds can release phosphates back into the water column when they become super-saturated. Some systems are able to absorb this with no ill effects. I would think that you would have algae growth on the sand bed if this was the case.

I think it seems to be a heavy bio-load for that tank, along with flake food. How old are your RO filters? Lights? I would consider adding some phosguard to your reactor with your carbon. This should quickly remove your phosphates.

I would replace your test. You will always wonder in the back of your mind if it is accurate.
Just my thoughts

Stray32 · May 14, 2010

Your title reminds me of Johnny 5

Get a TLF reactor and run Phosban. I haven't had readable phosphates since I set this up in my tank.

stunreefer · May 14, 2010

Vacuum your sand bed. Get a gravel vac, and do about 25% of the sand bed while siphoning the water into a bucket. Replace with fresh SW. Repeat the process everytime you do water changes. Your sand bed is not deep enough to develop an (efficient) anerobic area for denitricfication (if it is, you do not want to vacuum), so you should gravel vac it. My sand bed is 1/2" - 1" deep and I gravel vac with every water change, 25-50% of the sand bed. Since this is your first time don't exceed 25% of the surface area, and move onto the next 25% next time, etc.

Running GFO will surely help bring PO4 down, but you surely have a ton of detrius caught in the sand bed, waiting to be pulled out

beaslbob · May 14, 2010

Just to make sure let see if I understand the situation. You have 0 nitrates, a small amount of phosphates, a bio wheel, have been running the tank for 3 years, and are starting to get some nusiances algaes.

1) kill the lights untill the algaes die off, the resume with less duration lighting. So you find a point where things look nice but the algae does not return.

2) Add a very small amount of nitrates (less the 5ppm). (calcium nitrate or potassium nitrate are good choices).

To me it sounds like the tank may be "nitrate starved" so that corals, corraline, macros etc are not doing well but cyano and other plant life that do not require nitrates are blooming.

Just a thought.

Worth at most .02

Fragged_it · May 15, 2010

Junkie said:
Alright I have a couple of questions. I'm getting high phosphate readings with my salifert test. It expired in December last year. Do you think it is still fairly accurate?

I never use a test kit past it's retirement date. Bad test kits have caused me to chase issues for days before I realized I had a bad test kit...

Junkie · May 16, 2010

...ahhh good input haha. thanks for all the replies. I didnt think that flake would be no bueno, i've been using it for years. I just find it odd with how much water im changing PO4 be an issue, tds reading was fine too. im just going to have to replace the test kit then re-evaluate and pick up some GFO.