Lanthanum and vortex filter

[reefkeeper2]

I don't know how many in the club are using lanthanum for phosphate control, but I have been experimenting with it for many months. Presently I have not been using it very much because dosing vodka and zeo stuff keeps the phosphates pretty much under control. Also, when I was using the lanthanum, I couldn't get the phophates down to or below 0.02. I think I discovered the reason for this though, and found a really super effective way to dose the lanthanum with no chance of any precipitate going back into the water.
I have a vortex diatom filter. I use it anywhere from once a month to once a week depending on what I'm doing in the tank. When charged with norit powdered carbon it's unbeatable for polishing the water or removing organic or chemical contaminants. It's the same stuff they flush down peoples stomachs in the Emergency Room when they have OD'd on something. Anyway, I have been injecting the diatom filter with a diluted solution of lanthanum chloride at about the rate of 2ml per hour. The results have been the best I've seen. Phosphates went from 0.04 to 0.0 (500gal water volume)with a single treatment. Best of all there are no worries of any precipitate getting into the tank, and everything looked great . By the time it was finished, the output from the filter was almost nil, being glogged with the precipitate.
I think I couldn't get the phosphate levels down to where I wanted them before because some precipitate was still getting back into the water, even with the use of the 10 micron filter socks. This is also sooo much easier than filter socks.
There are probably not thay many people out there using a diatom filter, but this worked so well I figured I'd share the info.

 

[CaptainAndy]

Where do you get lanthanum from and how do you mix it. Despite the zeovit system, have a very high bioload and sometimes can't keep the phosphates down. Love to try this.

 

[Greg Hiller]

The lanthanum chloride is available from pool chemical supply houses. It's called Seaklear.

 

[reefkeeper2]

I take between 5-10ml of seaklear and mix it with 50ml of DI water. A syringe pump then doses 2 ml per hour into the diatom filter. The filter clogged before all was used up. The higher your phosphates, the quicker this will happen. The first time I did this the filter was clogged in about 3 hours. The second time it ran about 10 hours. Vortex diatom filters can be bought for less than $100.00. I have the DL model which is bigger and costs a bit more. I have been using them since I was a teenager which was a very, very long time ago

 

[Greg Hiller]

Paul, good to hear it's working well for you. I've been using it as well, though very conservatively thus far. It's interesting to hear that you were able to get the PO4 so low with it. I did not think it was possible.

For those of you thinking of trying this, syringe pumps are neat instruments, but VERY expensive. They are designed to dose very small volumes of liquid. For an application like this you could just as easily dilute the chemical in additional DI water and feed with a pump that is much less expensive.

 

[reefkeeper2]

I had the syringe pump left over from that feeding experiment I did with the non-photosynthetic corals. I think any dosing equipment could be adapted to work, even the gravity fed types. If you had trouble dosing at such a slow rate, all you would have to do is dilute the lanthanum further. I think the slow rate is key.

 

[CaptainAndy]

Started today. I have several kangaroo feeding pumps so I just diluted so I can run at 20 cc/hr. Are the dosages arbitrary? Did you use the diatom powder with the Vortex or was the bare filter bag sufficient to catch the precipitate? I added the powder.

Thanks,

 

[reefkeeper2]

Make sure you use the powder!20cc an hour is too much. I use 10ml of seaklear mixed with 50ml water and dose at 4ml per hour. In about 3 hours the filter will clog. Clean it out, fill with fresh powder (and carbon if you have it) and continue. If your phosphates are high you may have to repeat the procedure a couple of times. Phosphate levels will bounce back quickly if there is a lot stored in your rock and sand.

 

[Greg Hiller]

>Are the dosages arbitrary?<

Yikes, you are certain to crash your tank if you dose too high. Be VERY careful with this stuff. Please read all the threads on this.

 

[CaptainAndy]

I used the exact amount recommended but increased the volume of RODI because I don't have a feeding syringe pump and needed a rate of 30cc/hr. First treatment lasted for 2 hours, second for 10. Phosphates went from 0.02 to undetectable. My total volume (tank/fuge/sump) is a bit over 500g as well.

Again, where did you come up with this regimen? Seems to work well. Why is this not a more widely used technique? Cheaper and more reliable than GFO.

 

[reefkeeper2]

The use of lanthanum with filter socks has been around for a while, and I used it quite a few times. I got the dosages from some threads I read on RC and tried different amounts.The main problem was precipitate still got through and for some reason it just didn't lower the phosphates enough. Some of my livestock didn't like it either. I just thought up the use of the diatom filter a few weeks ago so this variation of the method is new. It is a huge improvement. I have dosed using this method many times now.