Algae Issues


New Member
This is the first time I am posting on here. I have been reading threads on here for about a year and have gotten most of my problems solved from other threads. I know there are quite a few threads dealing with algae issues, however, I wanted to get some insight on what I should do with the algae I have growing.
The first two pictures show algae that seems to constantly grow on the sand.
The third picture shows a dark green algae that is growing on my LR.
The final picture shows the whole tank. It is a 125g.
The inhabitants are:
20 hermit crabs
15 scarlet crabs
20 nassarius snails
4 emerald crabs
1 coral banded shrimp
5 peppermint shrimp
1 serpant star
1 Lawnmower Blenny (doesn't seem to go after algae anymore... really enjoys krill :notsure: )
1 Scooter Blenny
2 pajama cardinals
3 firefish gobies
The corals I have are:
Green Ricordea Polyp
Umbrella Polyp
Trumpet Coral
Green Eye Zoo
and one Anemone
Any help would be appreciated.



What kind of flow do you have? id say you need some more flow and a much larger clean up crew. About 20-25 more hermits, 25 turbo snails and 10-15 nassarius.
What kind of lightts and how long do you run them?


New Member
I have three powerheads (160gph), two of the overhang filters (don't know the flowrate), the sump has a return flowrate of approx 600 gph.
The lighting is:
(3) 250W MH HQI's.
(2) 96W 10000K/Actinic PC
(2) 96W Blue 450nm


how long do you run your lights? i had an algae problem when i would leave my lights on too i keep it at 10 may also want to increase your flow for that size of a tank turns over about 14x per hour and some people were recommending more.....i'm not the expert though.....just trying to help


New Member
I appreciate your help and any advice is great to have. I keep my PC on about 10 hours and the MH on about 6-8 hours. Also, any advice for the stuff growing on the sandbed? Would more waterflow fix that? I was thinking about getting a horseshoe crab, but I have not been reading good things about that.


Active Member
What are your nitrate and phosphate concentrations?
Do you use RO/DI water?
How often do you feed and how much?


WATER CHANGES! your nitrates are probably high, which would explain the algae. no clean up crew is gonna fix that. check your water levels, and if the nitrates are high, start doing 10% water changes every week (which you should do anyway... either at 5% or 10 %) and clean off what algae u can, it just helps the algae to go away faster. goodluck!


New Member
Ok, here are all my chemical specs:
8.3 PH
0 - 0.25 Ammonia
0 Nitrite
0 Nitrate
0 Copper
.5 Phosphate
When doing water changes I use RO water.
When replacing evaporated water, I use filter tap.
I do a 10% water change every 2 weeks, and replace evaporated water in between.
I use to have a terrible hair algae problem, then finally I took out most of the LR and got an OLD toothbrush to it. But within the past month or so, this type (whatever it is) of algae is propagating.


I would suggest NEVER using tap water. Filtered or not. The RO does a much better job of removing organics than the filter on the tap. Just make a few gals more Ro water after the water change and use that for top off. That may help.


You have low flow. I have a 50 gallon tank and I have almost 1500/gph of flow. You have a 125 with under 1000/gph. You should replace those tiny powerheads with a couple of big 800 gph power heads.


chris can you give more info on your filter system that you run in this tank. i saw top on the tank 2 big hang on filter , do you have any sump under ... it will help to advice if you can tell about your system.


New Member
Thanks for all the advise, I will definitely get better power heads and stop using filtered tap. I do have a sump underneath the aquarium, suppose to be rated for 150 gallon aquarium or 800 gph, OR atleast that is what they advertise.


Active Member
As others have said, only ever use RO/DI water; the filtered tap water is the source of your nutrients which is feeding the algae. Increasing flow will help as well.


Originally Posted by ChrisAg99
Thanks for all the advise, I will definitely get better power heads and stop using filtered tap. I do have a sump underneath the aquarium, suppose to be rated for 150 gallon aquarium or 800 gph, OR atleast that is what they advertise.
it's good that you have sump and i hope you have there refuge if yes put in the refuge cheato (planet ) it will help a lot. other one more important thing your pho4 level not good and Phosphate cause algae if you can add phosban reactor it will reduce the phosphate to 0.00 (by the way it's not expensive) , add a active carbon in the sump to. cut the light now and run them 6 hour a day . for sure use just with r/o water and you see the result soon. more then that i have 120 with 3 ph that run 2600gph each i suggest to you to add strong one to creat a strong circulation in the tank.hope you have protein skimmer it will help a lot.


Active Member
The two HOB filters look like Emperor 400's. Supposedly have a 400gph flow rate, but I wouldn't count on anythign close to that. I have one and love it, but not for water circulation purposes. You might want to try pointing a power head at any bad spots to see if that helps it to know if you need to add more flow or not.
About the phosphates (PO4s)... I didn't really have a problem, but bought a Two Little Fishies Phosban Reactor. I think it ran $40 online, but by the time I got the media, powerheads, fittings, tubing, and shipping, I think it ran me about $70. Great investment. It has a great build quality, and constantly keeps my PO4s at zero. I partially bought it to keep my live rock from absorbing so many PO4s cause I'm guilty on water change frequency to prolong the life of my tank (once the live rock absorbs so many PO4s, it gets saturated and you hit 'old tank syndrom'). Good buy and I'd recommend it. Can't really hurt either minus the budget =).
Tank looks good =), Good Luck!