Algae: Need a good quality phosphate remover.


New member
I have been using Pura Phoslock for the past 9 months, but still having some hair algae issues. What do you all use and recommend. I have only 30 total gallons to treat so I don't need huge quantity here. Thanks.

Readings are all:
t 79-81
ph 8.01-8.25
sg 1.025
mg 1265
ca 415-435
dkh 8.9-9.8
nh4 0
no3 0
po4 0

I have recently gone to a bare bottom tank as I was having nutrient export problems (had a shallow sand bed)... I am a 9 month reefer, so I guess I do have a tendency to feed too much. I have a medium stocked 20 gallon tank with both lps and sps corals, and 2 large groups of dendros that I feed twice weekly. I have 2 clowns, and a clean up crew or 3 turbos, 10 astraeas, 1 cerith snail. I am trying to get a good handle on over feeding my tank though. I feed the clowns daily a rotating schedule of frozen and flake. I feed the corals 1cc of Oyster Feast or Roti Feast or a pinch of DTs oyster eggs twice a week, the same days that I spot feed each of the dendro heads (there are about 25 to feed)

I have 220gph returning from sump, and MP10 on 1/2 throttle so probably providing another 700 gph in the tank... total 920 gph running through 20 gallon display tank. Total display tank turnover would be about 46x an hour.

I have PC lights. 2 x 65 watt bulbs. One is actinic and on for 8.5 hours a day, the other is a 10,000k on for 6.5 hours.

I use both an AC Remora and a Tunze 9002 in my sump for skimming. I also use a filter sock that gets changed every three days. I use carbon in a canister that I have running off the sump, and that is where I place my GFO too. I change the carbon every two weeks, rinse out the canister at that time as well. Inside the canister is only a handful of ceramic bioballs that I use to sandwich over the carbon and GFO bags to keep them from smashing around too much in the canister. I change the GFO every month.

I do a 20% water change weekly after blowing all the rock work off with a turkey baster.

Whew. :fun4:
Thanks all.
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New member
Ive used rowaphos in the past and it worked well.

Sadly, that's the only kind Ive ever used so I don't know how others compare.


New member
No you can't because it will become a hard lump you must use GFO in a phosban reactor to keep the partical moveing other wise it just gets hard and wasted BRS sells a nice recator for GFO and carbon you can get single chamber or dual

SC Trojan

New member
Can I use it in my canister filter? (I have it running off the sump with my gfo and carbon)

i mix mine with gac and run it in a powerfilter cartridge and never had a problem with it clumping. give it a try and if not the reactors arent too expensive, the only reason i dont is because i dont have a sump just yet.


Premium Member
Lots of people run GFO in a canister without problems. The reactors might be better, but that's hard to determine, and might vary from tank to tank.


New member
I see that BRS sells 3 types... granules (the regular GFO), the pellets, and the HC GFO (not sure but that looks like granules from the picture). Should I make a choice based on granules, or pellets for my canister? I know that the Pura Phoslock has never turned to a hard lump in my canister, but maybe BRS stuff is different.


New member
pura phoslock works just as well as the others but it needs to be in a reactor like all granular (use warner marine regular phosar pellets or bulk reef supply pellets if your not using a reactor). I used pura, others and high capacity and the only difference is the Pura (like some others) needs rinsing forever compared to high capacity and more is required to accomplish the same results. I've found that any benefits of those that work a little better are cancelled out by the price. all you have to do with those that are a little less effective is use more and because they are cheaper you same difference. I have used several brands and they've ALL done what they say they do....yet didn't magically solve my algae problems.

I think all maintenence/stocking is as ideal as it can get and doesn't sound like your grossly over adding nutrients. I'd do in this order: get a reactor (ViaAqua is only like $35 and works leak free and fine. perfect small size for smaller aquariums), manually remove as much as much hair algae as possible (tweezers work good for removing algae off work for me), feed the clowns every other day instead of daily, stop feeding flakes all together, target feed the dentro's but stop broadcast feeding the corals otherwise (really isn't neccessary to direct feed non photosynthetic corals when you have fish that are fed ESPECIALLY while going thru algae problems). stop using oyster feast and DT oyster eggs all together (those are appropriate size for sps and likely do more to foul water than help fatten LPS). if you have to have an algae problem hair algae is the one to have.


Premium Member
The pellets are physically stronger, which can be an advantage, but I think all three will work.

I agree that keeping feeding under control is a good step. The oyster eggs can feed a fairly wide array of animals, and I don't think a small amount is going to hurt anything, but if there's too much food in the system, that's one easy feeding to skip.


New member
Stanlalee, thanks for your detailed response.
The reason why I use the Oyster Feast is because I have SPS corals (montiporas) and a coco worm. Maybe I could use it only once a week and see how it goes, would that be enough for the corals? I didn't realize that the flakes could be a problem, so I'll stop regularly rotating that into the clown's diet. I really don't like the idea of feeding the clowns every other day though. I seen lots of people recommend this, but to me it seems too unnatural for a fish to go so long without food... in nature they feed constantly. And besides who can resist those cute little eyes looking out at me. ;) Maybe I'll look into a reactor, but I really don't want to pack up a perfectly good Eheim canister that cost me several hundred dollars less than a year ago before I set up the sump for my system. I'll continue with regular maintenance, and picking off the hair algae.

Wouldn't you know it yesterday I found a whole colony of bubble algae on several rocks in the back of the tank.... argh so now I'm carefully siphoning out those beauties!! If only for one week I could be perfectly happy with the tank and not see any problems. Maybe in a year!!!

Thanks to all for your advice.


Premium Member
Feeding every day is fine, as along as the amount is scaled appropriately. :) I'm personally not convinced that flakes are any worse than any other food as far as water quality, but my clowns did like the New Spectrum pellets better than most of the flake foods, so I don't have all that much direct experience. No matter what type of food is fed, someone will claim it leaches huge amounts of nutrients.


New member
I have stated I dont think there is any gross over doing it there with nutrients. I dont like flakes even if they were phosphate free because they dont sink well, go thru the overflow and well I just dont like flakes except for goldfish :hammer: I also dont think the oyster eggs are harmful or not being consumed however when fighting algae the benefits of coral geared food arent worth the possibility of potentially feeding nuisance algae knowing the corals will be perfectly fine in the absence of oyster eggs and other coral foods. those are things you add to enhance growth/color when there are no issues. I think a good compromise would be to target feed a small amount to the cocoa worms and montipora like you do the dentro's

as for feeding every other day: I dont believe fish that arent fed every day dont eat in a 9 month old established reef. there's natural prey and algae to get clowns and most omnivores thru the day. but like stated above if the amount is suitably proportionate every day or even twice a day is fine. most small fish are eating all day long in nature. we arent going to duplicate that in a nano reef. most people feed more than is neccessary for healthy looking long surving fish. my clown and wrasse are on 1.5yrs on every other day feeding (though I know thats no measure of health I dont anticipate them dropping dead anytime soon). SOME fish like tangs need an algae sheet every day IMO or anthias do better with daily feeding but clowns/damsels/small wrasses/basslets/pseudos arent what I consider fish that require daily feeding or cant find anything to eat in a reef tank between days.

Oh I've found these never ending problems often have more to do with luck of the draw (what you aquired) then right and wrong. weekly water changes, low fish stock, two skimmers, GFO ect are all the right things to do. I had a few set ups where I didn't do half as much as I do now with inferior equipment and practices and NO problems to speak of. Current tank: impeccable maintenence practices, low bioload, low feeding, superior equipment yet the only tank that I've had bryopsis, red turf, bubble algae, hydroids at one point or another. I think the good practices are the difference between plague levels and liveable but I didn't do anything wrong to get any of that stuff.
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New member
Thank you Bertoni, I appreciate your advice.

The clowns do love to eat the flakes out of my fingers under water, and since I turn off the return pump when I feed, none of the flakes actually go to the sump, unless of course I over feed... argh. :) I really do need to focus on quantity of nutrients going in and out of my tank. I had so much trouble with a SSB, even though I would vacuum it weekly, that I went bare bottom to get a hold of my husbandry. It has only been a week completely bare, as I removed the sand slowly over several weeks, but now I really can eyeball what is floating around the bottom of the tank after I feed. It can only help, plus I can turn up the vortech higher and not have sand blowing around, which was a problem in such a small tank. I do think that I can reduce my coral and dendro feedings to once a week, at least until I get things under control, and be very careful about how much I feed each coral.

I emailed BRS and asked them what they would recommend for GFO in my canister. We'll see.

I do wonder about luck of the draw. When I bought my live rock it already had a pretty good amount of coraline algae on it, so I wonder if it had been in someone's tank before mine. I could have inherited their set of problems. None the less, it is what it is, and I'll keep picking away at all the stuff that irritates me to no end. At least for now I can say the apitasia is under control... for now. :) This has been a real learning experience for me.

Thanks again.


New member
I have a question for all you guys running GFO. I'm always wondering why don't you guys use liquid po4 removers like blue life or brightweel? GFO needs a reactor, needs to be replaced, more expensive, needs maintenance, you need to clean the reactor and etc.. What's the big deal?
Lanthanum chloride or lanthanum carboxylate for orthophosphate
removal in seawater aquarium - a feasibility study

From this article:

"Filtration with 25μm mesh removed up to 15% turbidity only, whereas
filtration with 0.45μm GF filter reduced 100% turbidity. Similarly, 1.8 to 3ppm PO4
removed after the treated seawater filtered through 0.45μm GF filter only and no PO4
reduction after filtered with 25μm mesh. La(Cl)3 had no impact on pH, but both
La(gly)3 decreased 0.2 pH unit in the treated seawater."

Although all lanthanum compound tested can remove PO4
3- from seawater, the
efficiency of removal depends on the pore size of filters. Lanthanum compound could
pass through filters and increase turbidity inside pool. Barry and Meehan (2000) have
found lanthanum can cause significant mortality to Daphnia due to cloggin g filtration.
Small lanthanum particles passed into pool could also potentially be trapped by gill
lamellae of fish.
Therefore, application of lanthanum compound to an aquarium has to managed very
carefully and better to be conducted in a side loop equipped with high efficient filters to
avoid any potential adverse impact on aquatic organisms due to leakage of lanthanum
compound to the pool."
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