View Full Version : Algae bloom with each water change

12/11/2011, 09:13 PM
Wondering if anybody has an idea what might be going on with these algae blooms(brown slime) I get with each water change. Our local water supply is very high in phosphates & silicates so I have been using RO DI water knocks both down to less then 0.02 ppm still get outbreak with water change. Tank test at 0 for phosphates & silicates, nitrates are near 0. Now I'm pretty sure the lighting is part of this my tank is in our family room with large windows lots of natural light & this is where I want it to stay it's where we get to veiw it the most. The reason I know the natural light is playing a part is there is no outbreak in the lighted sump. But with that said the water changes are still what triggers the outbreak they always follow with in a day or two. I had this issue in my old home also where the tank was in the basement still got natural light but not nearly as much as now. Any thoughts? Thanks!!

12/11/2011, 09:28 PM
It can be the salt.. have you tested the new batch before getting into the tank?

12/11/2011, 09:30 PM
all the reefs of the world are lit by natural light, i really doubt sunlight is the root of the problem...however once established, all algae needs is light to flourish...

your tests will always read low or zero especially if there is algae present as the algae consumes any available nutrients before the kits can read it..

you say you are not using the city water but rather purchasing rodi? are you getting it from a LFS or a water depot type of store?

around here my city water reads 164ppt my ro unit takes that to 0....my local water depot sells ro water but it is still 5-10ppt ( i have no idea what those 5-10 parts are though)

anyway, we would need to know more about your setup up to help better...

how old is the system?
how much rock is in the system? where did you get the rock?
how much sand is in the system? where did you get the sand?
how many fish are in the system? what kind of fish? how are they fed?
how big is the system?
got any pics of the algae?
how are you filtering your system? skimmer? reactors? filter floss/bags? media?
do you have a sump? what is in it?
what is your source water? city? well? store?
do you have a calibrated TDS meter?

the more detail the better...pictures tell a thousand words...

FWIW...my tank is in the living room too, gets about 3-4hours of direct and indirect sunlight, no algae...

Randy Holmes-Farley
12/12/2011, 06:05 AM
Brown slime may be cyano. What salt mix? Does it contain organic matter? Some salt mixes may promote cyano for that reason.

It is possible that each water change stirs up detritus and temporarily makes nutrients available, including organics.

I is also possible that algae growth is limited in your tank by iron or something else your water lacks, and the water change temporarily eliminates that limitation.

12/12/2011, 11:38 AM
120 gal tank 40 gal sump filter socks on intakes to sump Aqua C Remora Pro & a Red Sea Prizm(from my old 72 set up) about 3" of aragonite sand in sump & tank. This set up is only about 4 months the 72 was transferred to it when we moved I also had this issue in the 72 the new tank did an initial bloom when first set up then cleared up nicely. Now with each water change get bloom worse than the initial. Hard to say amount of rock some has been added with move to bigger set up I would guess at least 80lb. Here maybe a problem though the 72 was setup for 8yrs about 20lbs of that rock were tufa could this still be leaching something into the tank but then why only after water change? The rest of the rock was live bought from a few different shops over the years. The water is from a RO unit at my wife's work(chem labs at PSU). I only tested for PO4,Si & NO3 cause I figured they would be the culprits,should I be testing for all TDS? The filters on the unit are change regularly I don't think I could get cleaner source water. Ph is also a problem I have trouble keeping it above 7.9 honestly if it wasnt for that I would just do less water changes so i wouldn't have to deal with the algae blooms. Live stock is Flame Angel, Starry Blenny, Tomato Clown, Royal Gramma,Red Hawkfish,Yellow Goby,Pistol Shrimp & 2 Skunk Shrimp/ Green star polyps,Actinodiscus Mushroom, Button polyps and a Rock Anemone. Feed Tetra flake & Spectrum pellets twice a day & small piece of Sea veggies Two Little Fishes. No additives I was thinking of doing a kalkwasser drip though to try to bring up Ph. Someone also suggested testing water after salt mix I will try this I have used both Reef Crystals & Coral Life Life.http://www.saltcorner.com/AquariumLibrary/browsespecies.php?CritterID=2057
There is a pic here of what it looks like I can try to get a picture of may actual tank later if this doesnt help. Thanks everyone

12/12/2011, 12:27 PM
Tank & sump also have macro algae in the tank the slime is even growing on the macro algae.

Randy Holmes-Farley
12/12/2011, 12:45 PM
Ph is also a problem I have trouble keeping it above 7.9 honestly if it wasnt for that I would just do less water changes

Well, I don't think water changes are helpful in dealing with pH issues, so nix that as a reason.

I'd also suggest switching to just normal IO since it has no organic matter and is a fine salt mix. :)

12/12/2011, 12:58 PM
OP - are you framiliar with cyanobacteria vs diatoms?

"brown slime" is usually referring to cyano, but I'm wondering if you might be seeing diatom bloom insted?

12/12/2011, 05:27 PM
RO water PO4 0.05 ppm Si 0
Coral Life PO4 0.05 ppm Si 0
So no change on these two I need a new reagent to test NO3

12/12/2011, 09:12 PM
How high is the phosphate level in the tap water? I don't think that phosphate level is horrible, especially given our testing limitations, but I might put a GFO reactor on the salt mixing container, to remove the phosphate before it hits the tanks. A lanthanum chloride product might be cheaper over time, although it'd require letting the water settle for a bit. I don't know how long that'd take.

12/13/2011, 12:50 PM
I think randy Holmes was on the right track. I think it is due to stirring up a realitivly new system, and biological development of the system is still building. I would start adding bacteria for starting up systems and with six fish start simmer use with a carbon source until nitrate go down to under 10ppm stop doing water changes cause you keep resetting the new tank load by disturbing the gravel.
Best of luck!