Lanthanum Chloride Dosing Instead of GFO

[FirstContact]

I am looking into Lanthanum Chloride dosing in lieu of GFO. I was thinking of setting up two reactors. One to drip the lanthanum chloride into, and the second filled with filter floss to filter out the precipitate. The effluent would then pass through small micron filter socks.

My question is, Can you set up lanthanum chloride and the RODI solution with a doser to drip dose 24/7? Has anyone done that? I'd like to take out the manual aspect of setting up an IV bag or drip container. I'd also like to know if you can do this 24/7 like GFO. If you run 24/7 what's a good ratio of lanthanum chloride to RODI water to start with?

 

[Cory]

I am looking into Lanthanum Chloride dosing in lieu of GFO. I was thinking of setting up two reactors. One to drip the lanthanum chloride into, and the second filled with filter floss to filter out the precipitate. The effluent would then pass through small micron filter socks.

My question is, Can you set up lanthanum chloride and the RODI solution with a doser to drip dose 24/7? Has anyone done that? I'd like to take out the manual aspect of setting up an IV bag or drip container. I'd also like to know if you can do this 24/7 like GFO. If you run 24/7 what's a good ratio of lanthanum chloride to RODI water to start with?

You could do that but not with anything else in the rodi.

The problem is once it uses up po4 it starts consuming alkalinity. That imo is very dangerous.

 

[Randy Holmes-Farley]

IMO, it is using alk all the time. Some of the lanthanum precipitates as lanthanum carbonate and some as lanthanum phosphate, or maybe a mixture of both together as calcium does.

I don't see a reason you cannot do what the OP is asking, but I've not heard of folks doing it, and I agree that too low of phosphate needs to be avoided by using low doses. I don't think the concentration of the lanthanum solution itself is critical, just the total dosed.

 

[FirstContact]

Thanks Cory, thanks Randy!

 

[Randy Holmes-Farley]

You're welcome.

Good luck.

 

[Dr. Reef]

It does use alk and phos at the same time.
I do have this setup in a 3 chamber reactor. Honestly floss does not stop it at all. I had to remove it and use 5 micron filter and change it every 15 to 20 days.
I use seaklear phos remover for aquarium and pour 2 oz in 1 gal of ro di water and dose 15ml every hour. 540ml per day, gal last 7 days. It keeps my phos levels under 0.03.
It also will drop alk like crazy so I have a good balance now even though I am using cal reactor I have to dose alk separately to match consumption due to lanthanum. It's a trial and error thing and will need to monitor levels every day till you find the sweet spot to balance alk consumption with lanthanum use. In my tank I have cal reactor at maximum flow with pH 6.35 and I still dose 540 ml of soda ash mixed in ro di water daily.
Why soda ash because lanthanum will also drop pH of tank to dangerous levels so i balance it with soda ash that brings it back up. I dose alk 15 ml per hour just after lanthanum, like I said its a balancing act and it can be done. Lots of testing and logs before u get it perfect.

 

[Dr. Reef]

Also I have the outflow of the reactor going directly to intake flow of my skimmer so whatever micron filter doesn't catch gets taken out by skimmer which is set to a bit on wet side to ensure.

 

[Dr. Reef]

It took me over 2 months of testing/trying to get all balance right. Now my tank sits perfectly at alk 8 cal 420 mag 1320 nitrates 0 phos <0.03 and pH swings are minimum 7.9 to 8.

 

[FirstContact]

Thanks Dr. Reef! That's great info if not intimidating! I really like the value of LaCl2 over GFO, but the balancing act appears to be much more complicated than I thought. I probably will still try it though! I'm sure I can be successful at it. Thanks especially for letting me know the filter floss is worthless. That was part of my filter plan.

If the filter floss stage is worthless, why do you use 3 stages in your reactor? Are the first two for contact time? Could you not just do 2 stages?

 

[Dr. Reef]

Your welcome
Floss does not stop it. 5 micron filter does. I use 2 chambers now for reaction and 3rd has 5 micron sediment filter.
Also I get my filters off ebay and are much cheaper than aquarium supply places.
Safe reefing.

 

[Dogtown]

Your lacl reactor sounds like a well tested method to control PO4 levels. I especially like how you are using 5 micron filters and then sending all of the output after the sediment filter directly into your skimmer. You are skimming wet as well. It really sounds like you've got this figured out for the long haul.

I've just started lacl dosing this week. My sump has 7 of the 4" sock chambers, which I'm now running with all 5 micron socks. I've been slowly ramping up the lacl dosage using a doser in front of the sock chamber and PO4 has dropped from .50 to .23 over the past 5 days. I will continue the process until it drops to .03 and then I'll adjust the dosage down for maintenance. No cloudiness issues on the glass or in the water column. No signs of stressed fish either. While my setup is working, yours looks like a better long term solution. I may add a reactor as you have done and send the output to my skimmer that way. I will also continue with the 5 micron socks. My water has never been clearer since I started using them and with 7 of them at work, they haven't really clogged up terribly fast.

Thanks for sharing your method.

 

[Dogtown]

Dr. Reef, here is the latest.

My method didn't work so well IMO. I was dosing directly into the 10 micron socks in the sump. The flow was fast and I think precipitate worked its way past the socks because I found a thin film formed on the glass soon after starting this. I had to remove the film with a razor blade. I discontinued the Lacl after that.

Differences:
10 micron vs 5 micron socks?
High flow vs low flow?
You used a reactor and sediment filter. I didn't?

If you have any new info about your own experiences or suggestions, please share.

 

[Dr. Reef]

New update:
After using lacl reactor for about a yr my phos levels in tank is stable under 0.02 always. So knowing that I made the following changes.
1.
5 micron was getting clogged too fast because at first I was using a lot of lacl. Now that levels are very stable close to 0.
I moved on to 10 micron sediment filter which last over a month but I change mine once a month.

2.
Previously I was using 1 Oz to 1 gal ratio dosing 1 gal over 7 days. Roughly 540ml per day broken down to 12 doses of 45 ml per hour.
Now I use a cap full (1/3rd of oz) in 1 gal of Rodi water. I also cut the dose and still cutting as I see phos levels stay stable under 0.03. Currently I am at 80 ml per day but I feel I will be able to cut it down to maybe 20 to 30 ml per day of extremely diluted solution.

3.
Not sure if I mentioned this before or not.
I had to make 2 changes to equipment.
A.
The little mag flow 5 pump I was using got coated with white film of lacl and quit working completely. Plus I noticed that as sediment filter got clogged, pump started pumping less and less. So now I have a feed to lacl reactor via manifold with a 2 hp 11k gph 220v pump which runs all my external equipment like chiller, skimmer, cal reactor, denitrator etc. It pushed water through even when 10 micron is super clogged. Also using this method allows no contact to lacl with any equipment or pump and dosing directly into reactor. (No cleaning of pumps or failure)
B.
I ran the output of the lacl reactor straight to feed of skimmer. This let's any white particles skimmed out if they made it out of the reactor.

Regarding the rate of flow through reactor. It's very very slow. I am going to guess about 1 gal of water flowing through reactor in about 3 to 5 min. It gives lacl a lot of time and 2 chambers to react before reaching sediment filter.
I hope it helps.

 

[Dogtown]

Yes, that helps a lot. Great documentation and easy to follow. Thanks for the recipe!

 

[Reeferdood]

I dose it directly into the top of the skimmer, dripping into the reaction chamber. Water stays much clearer this way IMHO...

 

[Dr. Reef]

Be careful with dripping it straight into skimmer. It will leave a very sturdy white film on everything it touches include the insides of the pump. Over time it will get thick enough to stop the pump from working.

 

[Reeferdood]

Be careful with dripping it straight into skimmer. It will leave a very sturdy white film on everything it touches include the insides of the pump. Over time it will get thick enough to stop the pump from working.

Worked like a charm for me..
I do clean the pumps every 3 months anyhow.. It seems like the best method with the least precipitation...

 

[FirstContact]

I've been dripping LaCl for several months now into a 10 micron sock. Using 20 mls SeaKlear to 1000 mls RODI. Never noticed anything escaping the sock, cloudy water, or abnormal behavior in fish. It's a few drips or less per second.

 

[bozo]

@Dr. Reef

I plan on doing the same exact method you are doing for the lanthanum reactor.

Just a couple of questions.

I have the same dose as yours but I'm trying to picture how I'd dose the LaCl into the reactor. From the pictures, it looks like you drilled a hole into the intake of the pump and stuck the outlet from the doser there.

Is this still how youre doing it?

I'm planning on having a separate reactor for lanthanum chloride exposure to the water. Then the effluent from that reactor will go into a 3 chamber RODI filter housings like you have. I'd just fill all 3 of those chambers with 10 micron filters.


Doser -> Manifold(water in)/LaCl Reactor -> 3 stage 10 micron filter each -> dump into filter sock (main siphon)

 

[Dr. Reef]

@iammrhappy
I changed a few things. In fact now after using LC for about 2 yrs all the phos has already been leached out I haven't dosed LC on over a month and tank is holding 0 to 0.02.

Changes I made were, i dropped the feed pump. Reason: I had LC being dosed in the intake of the pump then into the reactors. What that did is it coated the inside of the pump and the impeller with thick coating of LC. The pump quit working after a little while. So I just gave the reactor a feed from one of my manifold. And in that tubing that leads to the reactor I put a small hole just enough for the LC tubing to pass into. I'll try to take some pictures later on and post them here. Second change I made was I made the first two reactor Chambers as reaction Chambers and 3rd with the sediment filter and the output to the skimmer. Overtime it did mess with my skimmer's impeller as well so be careful with this stuff. Only tip I can give you is to diluted as much as you can.