po4 control with gfo

[dadonoflaw]

i have an iron based gfo but the water comes out at .03ppm. how do i get these numbers down. i have an active refugium that i regularly prun and i do weekly changes to keep it down and phosphates are 0 out of my ro unit. i cant get it below 0.1ppm

 

[kaskiles]

That 0.03ppm is probably within the error range of the test kit. If you see cyano or hair algae in the tank (and you don't want it), change the GFO, otherwise assume your GFO regiment is good.

 

[Randy Holmes-Farley]

How much are you using?

When did you last replace it?

How are you using it?

Do you have an algae problem?

 

[dadonoflaw]

i do have an algae problem. i am currently running it in my calcium reactor since i am not using it for that. i replaced it like 2 weeks ago. and i am using a little less than a gallon of media according to the bucket.

 

[Randy Holmes-Farley]

A gallon of GFO?

 

[dadonoflaw]

yea on bulk reef supply i got the gallon size container and i used almost all of it in the reactor. it says 4.5 pounds and i would say there is about 3 pounds in there. here is a link http://www.bulkreefsupply.com/Carbon-and-Phosphate-Remover-GFO-Phosphate-Remover-(GFO)-Pellet-GFO/c109_8_88/p34/One-Gallon-(4.5-pounds)-Granular-Ferric-Oxide-PELLETS/product_info.html

 

[kaskiles]

That sounds like a lot of GFO to run all at once on a tank.

I think that calcium reactors are designed to have a pretty low tank water through-put rate, but the GFO reactors recommend something like 80 gallons per hour. Can you double check that your calcium reactor output has a reasonable amount of flow going through it?

It might just be that the kit is reading 0.03 but the phosphate level is actually lower, and it's just a matter of time before the algae dies off. Although in my tank, just a little GFO (1 to 3 tablespoons) really seems to put a visible dent in hair and cyano in about 1 weeks time...

 

[dadonoflaw]

well i have a mj1200 going in. i turned off the recirc pump. do you think i should turn it back on. would that help? it comes out as a continuous stream like an ro tube. it filled 2 cups of water in 15 seconds. just today i noticed more algae growth. i also have macro growing in the fuge but i guess its not keeping up.

 

[Randy Holmes-Farley]

I agree that a gallon of GFO seems way out of line too much if this is for your 180 gallon tank. Did someone suggest that much? How long have you been using it?

How are you measuring phosphate?

 

[dadonoflaw]

i just put alot in because i couldnt get the numbers down. no particular reason. i just put it in like 2 weeks ago. shouldnt it work right away? i am using a salifert test kit to measure my levels. also should i run the recirc pump for better results?

 

[Randy Holmes-Farley]

My guess is that the Salifert kit may have bottomed out, and won't read accurately at that level or lower. Reading levels lower than 0.03 ppm is challenging for any technique that reefers use at home.

 

[dadonoflaw]

so what can i do. my DT reads 0.1ppm and i need to get it lower than that. should i remove some of the media?

 

[Randy Holmes-Farley]

Does that kit read 0.00 ppm in new salt water? I have difficulty thinking that a gallon of GFO is leaving 0.1 ppm phosphate in the water.

 

[boxfishpooalot]

Gfo works. Forget what your test kit is saying. dont expect to get it all out in one shot. You need somthing to remove the algae too. Its going to grow in every tank. Its the lowest common denominator of aquariums. You cant stop it, because phosphate continually rises.The difference in tanks without algae and with algae are phosphate control and algal removal teqniques. Some control phosphate well, others let it build up and then replace the gfo. While others forget the gfo, but have so many organisms to eat algae like snails and crabs that the algae never takes off!

My adivice is to get some critters to eat algae so it has less chance of survival. Both predatory animals and chemical removal of phosphate replaced on a scedual.So your obviosly slipping on one of those things.

 

[kaskiles]

You might also want to switch to a regular GFO media reactor (BRS or TLF) that you can get a little more flow through, I think you're at 30 gph and could go higher. I would not turn on the recirculating pump, just because I don't really think it would do much but burn electricity...

 

[dadonoflaw]

i tested again last night and it finally came down a bit. i dont understand why it was so hard at all since i have 4 fish in a 180 and i barely feed. dont know where it is coming from. i did the higher sensitivity test and got .015ppm which is what i like to see. thanx for the help guys. i had tangs for that but a recent kalk disaster screwed that up