Aquarium Water Testing test results

[SteveM]

I decided to send off a water sample to Aquariumwatertesting.com to see how their results matched up to my test kits. I have also been have a little bit of a problem with brown diatom algae and have not been able to figure out why. Here are the tests and results.

 

MY TESTS

Calcium..............................456.......HACH Kit

Calcium..............................380.......Seachem kit

Alkalinity.............................9.8.......Instant Ocean kit

Alkalinity............................11.5......Salfert kit

Magnesium........................1410......Salfert kit

Nitrate...................................0.......Salfert kit

Nitrite....................................0.......Salfert kit

Phosphate..........................0.03......Hanna Phosphate meter

 

Aquarium Water Testing Results

Calcium..............................388

Alkalinity............................11.8

Magnesium.........................1425

Nitrate..................................0.7

Nitrite................................0.005

Phosphate...........................0.03

Also tested

Silica...................................1.0 (High)

Potassium...........................346 (Low)

Boron..................................3.0

Strontium............................9.1

Iodine.................................0.06

Copper...............................0.01

Molybdenum.......................0.00

Ammonia...........................0.001

 

 

Overall I thought the results were pretty close except for the HACH calcium test. I thought that was supposed to be a very accurate kit but the Seachem was much closer. (Almost exact.) The best information I got out of this was that my Silica levels are to high. It says that could be as a result of my RO/DI water but I have been keeping the filters replaced and put some new ones in only last month. It also says that using a commercially available phosphate remover may help but I run a reactor with carbon and PhosBgone so I'm not sure what else to do at this point.

 

Anyone have any suggestion about lowering the Silica levels???????

[ctenophore]

Silica...................................1.0 (High)

 

Anyone have any suggestion about lowering the Silica levels???????

 

Do you think the diatoms are growing due to the silica? Is the brown stuff just a light dusting of brown on the sand, or stringy snotlike brown algae? The latter is often thought to be dinoflagellates. I think only the powdery brown stuff (diatoms) use silica, but I may be wrong. Usually both of these are associated with new tank syndrome or a sandbed/rock disturbance, but yours has been set up for a while, right?

 

You should send them a sample of your RO/DI water and see what the silica level in there is. That would explain the buildup in your tank water.

 

Have you looked at that new type of high efficiency GFO, that looks more like carbon?

[CHUBAKAH]

I've seen lots of discussion lately on RC, and from what I am reading the whole connection between diatoms, and silica is urban legend. I'll post the links if I run across them tonight when I am on there.

[Rascal]

Kind of like Ctenophore suggested, perhaps a bit of experimentation might be in order. Test your RO water but also your freshly mixed saltwater (to see if the salt mix might be the source) and the output of your GFO reactor (to see if it is actually removing the silica like it should). Rather than sending a bunch of samples to aquariumwatertesting.com, it might be cheaper to get a few hobbiest silica test kits and hopefully find one that accurately matches the 1.0 result they got on your tank water.

 

I haven't tried the GFO from bulk reef supply yet, but my experience with Phosar's HC vs regular GFO was that there was quite a difference in quality, with the HC type being more like Rowaphos.

[ctenophore]

I've seen lots of discussion lately on RC, and from what I am reading the whole connection between diatoms, and silica is urban legend. I'll post the links if I run across them tonight when I am on there.

That may very well be true and it wouldn't surprise me. There are definitely some phototrophic microorganisms out there that do make silica bodies, but I'm not sure if the "diatoms" we see in brown films in our tanks are in that category. True diatoms use silica, as do radiolarians. But whether elevated silica levels in a reef tank would trigger some of these to grow out of control may very well be urban legend.

[dshnarw]

That may very well be true and it wouldn't surprise me. There are definitely some phototrophic microorganisms out there that do make silica bodies, but I'm not sure if the "diatoms" we see in brown films in our tanks are in that category. True diatoms use silica, as do radiolarians. But whether elevated silica levels in a reef tank would trigger some of these to grow out of control may very well be urban legend.

 

If the conversation on RC is as I expect, I think some other nutrition source is the limiting factor in their growth instead of silica...and I'd guess a likely suspect would be iron.

[Highland Reefer]

Are you sure they are diatoms and not a bacteria? I would not put much faith in AWT results. Their equipment is not the best for a so called professional company. You get all of the tests done from AWT for the cost of just one test from a truly professional company using good quality equipment. Every test I have seen from them, comes back with high Silica levels. Do you have access to a microscope?

Edited November 19, 2008 by Highland Reefer

[treesprite]

How do people get copper in their tanks without actually adding it?

 

When I saw teh silica result I immediately thought about diatoms. I think what I have read in the past isn't that silica doesn't contribute to diatom growth, but that silica sand does not leach silica into the tank.

[flowerseller]

Is the brown stuff just a light dusting of brown on the sand, or stringy snotlike brown algae? The latter is often thought to be dinoflagellates.

I have a perfect mental picture what you're talking about, so much so I think I can actually see it and mentally siphon it off!

Keep it siphoned off with a small clear tube attached to a small diameter hose.

 

I believe most are best served using PO4 removers for a day or two with slow flow and removing.

Keeping them in the tank constantly often releases it back into the water.

[Origami]

I've seen lots of discussion lately on RC, and from what I am reading the whole connection between diatoms, and silica is urban legend. I'll post the links if I run across them tonight when I am on there.

Diatoms use silica in the construction of their cell walls and other structures. It's not terribly surprising, either, that some form of life would do so. Silica is a very common inorganic compound found in the Earth's crust.

[dshnarw]

How do people get copper in their tanks without actually adding it?

 

When I saw teh silica result I immediately thought about diatoms. I think what I have read in the past isn't that silica doesn't contribute to diatom growth, but that silica sand does not leach silica into the tank.

 

 

you do add it...every time you put new saltwater in the tank. Without any copper whatsoever, you'd kill most of the fauna in your tank, just as with too much.

[treesprite]

you do add it...every time you put new saltwater in the tank. Without any copper whatsoever, you'd kill most of the fauna in your tank, just as with too much.

I did not know this (as you could tell) - thanls for the education

[SteveM]

The brown stuff in my tank is usually like a cross between a dusting and the stringy stuff. It's not real bad and it only shows up on the sand about a week or so after I do my bi-weekly water changes. I also get a very little on some of my rocks. I usually clean it all off when I do my water changes. As I said it's not real bad but just bothersome.

 

I have been trying to figure out the cause of it and that's why I sent off the water sample. I did the one time test just see what they had to say. I guess I'll just keep doing what I'm doing and maybe run a little more of the PhosBgone in my reactor to see if that helps. Any suggestions for the right amount of carbon and GFO in a reactor? Currently I have been using about 1 1/2 cups of PhosBgone and 2 1/2 cups of carbon.