I am doing some testing of phosphates and GFO performance, origonally this got started under “how often do you test your waters” but figured it needs to be in a post of its own.
I just ran a preliminary test on phosphate using an API test kit then a Hach DR 890. Interesting is all im willing to say at this time…
Samples were taken from my freshly set up uncycled 40 long, and my 10 gallon before and after a water change. The water used to change out 10% of the 10 gallon was from the 40 long.
Turbidity API HACH
Tank pH Alk NTU Po4 Po4
40L 7.93 155 1.18 1.0 .06
10 gal
pre w/c 8.03 116 .275 .5 .47
10 gal
post w/c 8.01 123 .874 1.0 .36
After collecting my samples I added 20 grams of GFO to the filters in the HOB wisper filter of the 10 gallon, I will be testing over the next few days and recording the results as well as refining the testing.
nice testing i’d like to see a hanna in there too lol. how about testing the water coming out of the filter with the gfo to see how much the gfo removes in one pass. This is good info thanks for sharing
[quote=“dunk, post:2, topic:4853”]
nice testing i’d like to see a hanna in there too lol. how about testing the water coming out of the filter with the gfo to see how much the gfo removes in one pass. This is good info thanks for sharing[/quote]
I was just sitting here thinking the same thing, best off having a reactor to do an influent vs effluent. That way you could calculate out the contact time with the gfo vs flow rate.
Anyone know what the c.t. should be on the gfo?
Well, one way to rationalize the GFO usage, is to just put a whole lot of it in a bag in the flow return path, trickle filter, or reactor and let it do its job. GFO takes PO4 down to a certain low PPB, and thats as far as it can go. then watch your hair algae and stuff disapear . It will last a long time per charge. not much measuring involved. it just absorbs PO4. test now and then.
lol kaptken, I know where your coming from and yes that works, but what your suggesting is to drop a nuke on a ground hog. Sure the ground hog is gone. But at what cost?
What id like to do is test the efficency of the p0[sub]4[/sub] removal based on the level of p0[sub]4[/sub] in the water with regaurds to flow rate and volume of GFO. By doing this one would be able to determine the amount of GFO required to reduce the p0[sub]4[/sub] to a “tollerable” level, and how long it would take…
Yea, ive had a few beers LOL
The API test kit still looks to be .5, need to throw that pos kit in the trash.
I also did a little experement with ferric chloride for removal as well. The test was pretty much botched. The Fecl didnt settle out the way I expected it to so I had to suppliment it with a polymer flocculant. The turbidity was high at the end of the test and the water had taken on a bit of color, this may be due to overdosing the Fecl. When I tested the sample small particles of Fecl were present which turned into blue crystals in the bottom of the sample. I would have to assume that when the test was performed the PO[sub]4[/sub] captured by the Fecl was released back into the water (from the acid addition) and gave a reading…
Test parameters
Starting PO[sub]4[/sub] .26
Fecl addition 2 ml of 1% solution to 500 ml sample
polymer 1 ml 50% concentration
Mixed at 200 rpm for 3 min than mixed 2 min at 20 rpm, stopped allowed to settle for 20 mins
Results
PO[sub]4[/sub] .13
NTU 2.21
I need to refine this process a bit more, maybe running a ferric poly blend and some post filtration to remove any floc that is still in suspenson. It shows promise Just need to run a few more tests and refine the process. This isnt something for the average reefer to run on his tank. Its more for a large (10,000 + gal) system, or for treating natural sea water.
Now i just need some water with high phosphates to experiment with. So if your doing a W/C and are local to the stanton area LMK as i would like to have your water…
I will be testing the 10 gallon water again on friday to see how much more phosphate has been removed by the GFO so stay tuned....
I messed around with phosphate removal calculations a few months ago, wanting to know the same thing about optimal flow rates regarding media and contact duration. Being that there are too many variables, and phosphate not being a major problem in my tank, I simply gave up. :SURRENDER
Kudos to you on your ambition, hope you come up with some definite numbers! lol YahoO
sounds like yous guys have some labs. Have you done any testing of LaCl ? I drip a very dilute solution of that at times to knock out any PO4 build up. but i forget if it takes PO4 ppb to a level lower than GFO does or not. once the Lanthanum binds the PO4, its prety much fixed, and insoluable. removed by protein skimmer or filter floss, or settles into sand. no problem.
[quote=“kaptken, post:9, topic:4853”]
sounds like yous guys have some labs. Have you done any testing of LaCl ? I drip a very dilute solution of that at times to knock out any PO4 build up. but i forget if it takes PO4 ppb to a level lower than GFO does or not. once the Lanthanum binds the PO4, its prety much fixed, and insoluable. removed by protein skimmer or filter floss, or settles into sand. no problem. [/quote]
No experence at all with lanthanum, not sure how to go about testing for it, or if there is a test kit available.
LOL great something else to research verdict_in
Ok I was a little late collecting my sample, so this is 100 hours after the 20 gram of GFO addition.
pH ntu alk po[sub]4[/sub]
8.14 .449 100 .16
The alkalinity drop is pretty interesting, I know that when useing Fecl for every 1ppm you dose it consumes 1 ppm alk. I wonder if the alk drop I am seeing is related to the GFO addition?
I’m not sure if thats a big alk drop by your fancy pants measuring. compared to your 10g pre/ post w/c’s it doesnt seem like too much. Maybe its just the coraline growth sucking it up. My system started sucking in the alk soon as i saw the first traces of coraline.
[quote=“saltcreep, post:13, topic:4853”]
I’m not sure if thats a big alk drop by your fancy pants measuring. compared to your 10g pre/ post w/c’s it doesnt seem like too much. Maybe its just the coraline growth sucking it up. My system started sucking in the alk soon as i saw the first traces of coraline.[/quote]
It could be, im having some excellent coraline alge growth…
[quote=“aonemarine, post:12, topic:4853”]
The alkalinity drop is pretty interesting, I know that when useing Fecl for every 1ppm you dose it consumes 1 ppm alk. I wonder if the alk drop I am seeing is related to the GFO addition?[/quote]
I am no chemist at all and this is one of my weakest areas. I took a ton of chemistry classes just for fun because it was a challenge. I was probably the only one in my organic chemistry class taking it for fun.
I had thought phosphates were a part of the alkalinity. Sure if carbonates are being pulled by organisms in the tank your alk will go down, but if you suck out the phosphates it will gone down as well right?
Again chem is my weak spot.
[quote=“aonemarine, post:7, topic:4853”]
The API test kit still looks to be .5, need to throw that pos kit in the trash.[/quote]
Some one’s making a lot of sense. I like this guy.