DSB Cause Phosphate and Hair Algae?


New member
I have a 150g reef with about 150lbs of LR and about 200lbs of LS (400w MH 20k). I have a 120g sump connected with a refugium section, which I have about 80lbs of LS, ~6" deep (PC 96W 10k/4k).

I have a terrible case of hair algae that I haven't been able to keep up with.

I've tried a whole bottle of algaefix marine, which seemed to only slow the hair algae growth. At the same time, the algaefix seemed to stunt my large ricordia and killed almost all of my chaeto.

My phosphates are .5. Nitrates 0, pH is 8.4

I've had some people tell me a DSB could contribute to accelerated hair algae growth and wondering if any have found truth in this.

I have three return pumps and two internal power heads in the display producing a ton of flow.

I'm thinking about two things, reducing the sand in my display and try only a DSB in the sump in addition to beefing up my cleanup crew (I'm very light on hermits, stars and snails).

I appreciate your opinions.


Marquis de Carabas
A DSB after time can become loaded w/ PO4 and contribute to HA problems. THe fact that you have readable PO4 tells me this is probably a nutrient in/nutrient out issue. A DSB can make it harder to remove all the detritus from the tank versus a BB tank.

Cleanup crews are important but everything they eat they poop back out, so they are not really removing anything. I would look more towards your filtration and your feeding to resolve this problem.


New member
I just added carbon in the sump, not sure if that will help or not.

I have a porcupine puffer and think that his feedings might be contributing to the phosphate issue since he shreds the food and creates a mess.

For filtration, my tank drains through a sump sock and have a skimmer that's removing some good green stuff every couple days.

Any suggestions on improving the filtration like you suggest?

Shane Hoffman

New member
Carbon in the sump isnt going to help much. Can you run carbon and GFO through a reactor? It is much better to force wter through the media as opposed to letting water flow around it.


Marquis de Carabas
Puffers are definately messy eaters and make it a bit tougher to keep clean. How often do you change you filter socks? After about a day (or less) the things they trap can begin to break down. WHat kind of skimmer is it? It may be a case of insuffient skimming.

If you have a big skimmer you can look into carbon dosing (vodka, sugar, etc), you can look into adding a refugium, a phosban reactor or other means of running GFO, or even a denitrator (made to remove nitrate but folks generally see a reduction in PO4 as well). Or you can look at increasing water change schedule or reducing your feedings. Depending on what you are feeding a good rinse can help as well.



Marquis de Carabas
<a href=showthread.php?s=&postid=15465515#post15465515 target=_blank>Originally posted</a> by ceemonkey
What is GFO?

Granular Ferric Oxide. It is a filter media that absorbs PO4. It really needs to be run under certain flow conditions to work well. If you just throw a bag in your sump it does relatively little good. It sells under trade names like Phosban and Phosorb. You have to be careful as too much of it makes corals more sensitive to light.


New member
The carbon I added is in a baffle in my sump and it stretches across the entire baffle, so water is forced through the carbon.

I have some Chemi-Pure, but I don't see it mention GFO. I don't have a reactor, but would be interested in any DIY links. I have found some DIY links on RC for calcium reactors, but not sure what the difference is.

Sugar Magnolia

Mother of Dachshunds
Staff member
RC Mod
The regular Chemi-pure doesn 't contain any GFO. The Chemi-pure Elite does. You can pick up a Phosban reactor for pretty cheap to run some GFO if you want. I just toss a bag of it in my filter along with carbon and Chemi-pure Elite. Seems to work fine like that for me, but from my understanding, running it through a reactor will get better results.

I think your best bet is to remove the rocks that are covered in HA and give them a good scrubbing, rinsing them in a separate tub of tankwater before placing back in the tank.