I like algae...? +substrate Q

[Liz]

Part of it laziness, I'm sure, but my brackish-going-marine, 1.014 sg, 50 gallon GSP tank has been getting the translucent orangey brown algae for a while now, which I think I like on the "reef bones" (from big al's online) I have in there... it looks more natural? I've been keeping all algae off the glass, of course... but then the past few weeks or so I've begun to get a bright green slimy algae on the tops of the "reef bones" and I don't know what I think of it. It'd be a pain to have to disassemble my structures to clean it off every so often, and then the areas would be bright white and I almost think I like the brown algae coating better than the raw white rock... any suggestions? Does anyone else find algae somewhat decorative (besides the purple/coraline or whatever, of course)?

Also, how thick should my substrate be? It's mostly crushed coral with some aragonite and about 3" deep at the deeper sections... isn't shallow substrate better for nitrification or something?

Edit: PIC!

One one hand, it's looking kind of grungy. On the other, I don't know about routine algae killing, and in a way I sort of like it (except maybe the green).

[lisalisa]

Deep sand beds can aid in NNR (natural nitrate reduction). You should google that on WWM. Shallow sand beds are easier to clean.

It's funny you say you like the diatoms on the Big Al's rock..so do I! It looks better now than it did stark white. I don't have any green though, and my rocks look a little different.

[Liz]

I don't think it's diatoms, aren't they the little opaque round bits are harder to scrub? This is the looser, "gentler" stuff that I think is actually algae...?

You say yours looks different? Probably because I also have thrown in there some liverock bits I got for free from the LFS... I was looking to set up a 10 gallon salt but figure I don't hardly have any money as it is.... so I put them in that tank. Don't know if theyre "live" anymore from the salinity change, but it's more rock....

[lisalisa]

Diatoms are stuff that comes off really easily.

[Liz]

Ohh... Hm. Aren't diatoms crustaceans or something? At the LFS we get these opaque, hard circular things that are harder to remove, and then the loose film of similar color. A guy who works there told me that the hard crusty round spots are just when the loose film builds up, but they seem like two different things, to me.... though I could be wrong.

[Phaedrus]

diatoms are brown algae that use silicate to make their "shells". there's lots of info around about it that can clearify it a lot better than i can.

The green stuff you have in that pic sort of looks like blue green algae. doing a search for that will yield a lot of info too. BGA means there is something wrong wit your tank. Can mean there are decomposing foods in the substrate, and/or not enough current and too much light.

[puffergeek]

Diatoms usually refer to algae that is unicellular. I've found the easiest way to get algae off rocks by attaching an old (very clean) toothbrush to the end of a narrow hose... I use the small rubber bands that the LFS used to tie my purchases with. It you find the "sweet spot" (bruch head about an inch and a half from the open end of the hose) where you can scrub and the hose sucks up the gunk, it works well.

I also don't mind some algae in my brackish tanks as long as it doesn't try taking over everything... it looks really nice on the (fake) mangrove roots. With puffers invert cleaners are usually food, but good ol' black mollies do a decent job and can handle brackish or marine conditions well.

[The Bruce]

i had a hard time with red slime algae, i would take it out and the next day it was back even stronger....turns out my tap water was filled with phosphates which were giving my algae a buffet. So i threw in a phosphate remover media and overnight the algae disappeared, now i only use RO for salt tanks....but you said you like the algae so i guess you don't need my advice

[Liz]

I'm reading about slime algae and how it's actually cyanobacteria. I'm reading that it raises nitrates or something?

What are phosphates and where do they come from? If I have them in my tank, does it necessarily mean my tap water has them?

[lisalisa]

Phosphates can be present in tap water, yes, but don't have to come from there. They also come in through food.

[Liz]

I've been having problems with my nitrates, and I think that may be what's causing this outbreak. Upon my reading, I'm thinking crushed coral may be the culprit, with large grains trapping waste and stuff. I have added some aragonite sand on top, could I stir it in with the crushed coral to fill in the gaps? Could I take some of the crushed coral out and smash it up into finer pieces/sand?

[RTR]

Eutrophic (high inorganic or organic nutrient load) water is always an invitation to algae. The particular type which takes advantage of the pollution is highly variable with the particular condotions in the tank and with the lighting.

[Liz]

I have all my "reef bones" rock bits scrubbed down and sunning in the driveway. I'm also doing about a 40% water change and removing maybe 1/3 of the substrate... I'm guessing a thick layer of crushed coral isn't a good idea.... If I have mixed crushed coral and aragonite, how thick of a layer should I have...? I know thick substrate layers can be good but I think mine was trapping more gunk than helping.

[RTR]

In BW & SW, I am of the minimal substrate school (actually in unplanted FW as well), just enough to cover the bottom - ~1/2" - and to be easily cleaned well. I commonly do prefilered RFUG on such setups as well, just for extra insurance. I learned long ago the more than the minimum substrate always promotes pollution by serving as a great nutrient reservoir. Deep sand beds or plenums are different things, but those I prefer to have in sumps or other connected tanks/refugia, not in the display. If you do not "need" it, it is likely to be generating extra upkeep for no valid reason.

[Liz]

Well I wish I had knew what a hassle it would bring before I bought all that substrate. I feel bad just throwing it away...