Pool sand substrate and brown algae

[DiscusBR]

In March I started my 80g tank. The set up: one 2217 Eheim canister filter and 2 sponge filters; one 54W T5 lamp; pool filter sand as substrate; some Manzanita driftwood and plants (no CO2). I have been doing three to four 60% WCs per week. The tank is not close to a window and is therefore not exposed to direct sun light. Soonafter setting up the tank, I started getting brown algae. Things got out of hand recently when I had to leave town. I just came back from a 32-day trip. In this period, lights were on for 5 hours/day and a friend did four 60% WCs. When I came back from the trip, the brown algae had taken the tank over. I tried cleaning the Manzanita driftwood but the dark brown color, almost black, will simply not go away. It looks horrible now. I basically lost great pieces of driftwood. In the water section of this forum, it was suggested that I should test my tap water for phosphate and silicates. However, after browsing the web, I noticed that some people argue that pool filter sand always contains silicates, a key source of brown algae. Is it true? Can my sand substrate be the culprit? Anyone with similar experience?

Also, some websites say that to fight brown algae you should decrease lighting, others say you should increase. What is the relationship between ligthing and brown algae?

Thanks in advance.

[raidendex]

The sand probably is silica based, so yes it would help diatoms in a way, but silica is not the only thing diatoms need. They create the hard outer shell out of it as a protection layer, some look pretty cool :) , but they do need actual food resources to thrive - nitrates, phosphates. Reading of zero for both in your tank with a lot of brown algae preset would be in a way wrong, since diatoms are basically using it all up as soon as it's available.
I would start with a test of your tap water for nitrates and phosphates, apparently phosphates can be quite high in tap water usually. If you do have high phosphates, RO DI might be an answer though seems like a lot of work or perhaps running GFO would be an easier solution, that would absorb phosphates. http://www.bulkreefsupply.com/store/products/carbon-and-gfo/bulk-gfo-granular-ferric-oxide-phosphate-remover

And finally - my albino bushynose pleco seem to like the brown stuff, had some on the leaves and around the tank before I got one, but ever since he was introduced to the tank, I never see a spot of it anymore.

[DiscusBR]

Ok, I bought a Sera Phosphat test kit today (quite expensive here in Brazil). Here is what I got: only 0.1 mg/l in my tap water. I got higher levels in my fish tank: 0.5 mg/l. So can these levels cause brown algae booms? According to the test kit, fish tanks should not have more than 1.0 mg/l. So it seems that my phosphat levels are normal (although I cannot explain why levels are higher in my tank than in my tap water). Any thoughts?

[Offpath]

How long is your light on for?

[DiscusBR]

How long is your light on for?

In the 32-day period of my absense, the single 54W T5 lamp was on for 5 hours per day. I am leaving lights off for now.

[x2h]

if you can get those feeder gold fish (here it's $0.20 each) throw 10 of them in there, see if they can clean it up for you. Don't feed your fish. This has worked for me. Good luck.

[Darrell Ward]

Your Manzanita wood is not ruined, it's normal for it to turn dark underwater, diatoms or not. Messing around with lighting usually does nothing to prevent diatoms, unless you use lighting so intense the diatoms are replaced by green algae. Otos sometimes eat diatoms, but may enjoy sucking the slime off your discus even better. I would just wipe down the tank during water changes and forget about it. Chances are, the diatoms will decrease or disappear altogether in about 6 months as your tank matures.

[DiscusBR]

if you can get those feeder gold fish (here it's $0.20 each) throw 10 of them in there, see if they can clean it up for you. Don't feed your fish. This has worked for me. Good luck.

Thank you for the suggestion. I had never heard of gold fish being good algae eaters. I don't want to get new fish due to the risk of introducing new patogens/problems to the tank.


Your Manzanita wood is not ruined, it's normal for it to turn dark underwater, diatoms or not. Messing around with lighting usually does nothing to prevent diatoms, unless you use lighting so intense the diatoms are replaced by green algae. Otos sometimes eat diatoms, but may enjoy sucking the slime off your discus even better. I would just wipe down the tank during water changes and forget about it. Chances are, the diatoms will decrease or disappear altogether in about 6 months as your tank matures.

Thanks. I know that drifwood will change appearance, but I see so many mature tanks where they look much better than my "black" pieces of wood... I will try changing the setup with other pieces of Manzanita that I have and will try to get rid of the algae with good maintanance as you suggest.

Can someone please comment on the phosphat readings that I got for my tap water and for the tank? Do they look normal?

[x2h]

[QUOTE=DiscusBR;780798]Thank you for the suggestion. I had never heard of gold fish being good algae eaters. I don't want to get new fish due to the risk of introducing new patogens/problems to the tank.[QUOTE]

if you have another tank, put your driftwood in that tank and let the goldfish clean it up. then treat your driftwood and put it back in the discus tank. as for the diatom on the glass, just wipe them off. good luck.

[DiscusBR]

An update: My brown algae problem has disappeared completely and very quiclky and I am pretty sure what the problem was. Before doing a big cleaning of the tank, I took out the Manzanita pieces and the few plants I had. Since then, I have not seen any algae development. Thus the problem was not in the pool filter sand substrate. I am convinced that the source of phosphates that was feeding the algae was the five planters that I was using from this company:

http://ripariumsupply.com/?page_id=45

These planters come with substrate and a feel fertilzing pellets. I am pretty sure they were the source of my problems.

I am rescaping my tank with new Manzanita driftwood and I will not have plants in the tank anymore. I just want to avoid problems in the future, especiially during my frequent trips.

[x2h]

glad you solved the problem!