Di/ro Water For Brackish?

[Synirr]

I know it's not recommended for freshwater and is for saltwater, but what about brackish? I ask because my tank is going be in front of a window, and although the blinds are always drawn it's still gonna be getting a little sunlight, so do you think using RO would help keep algae down?

 

[nmonks]

Using "pure" water in a brackish tank, as opposed to that from the municipal supply, is probably pointless. As you probably realise, the extra hardness in tap (faucet) water is a good thing in a brackish tank, where a high and steady pH is desirable.

As far as combating algae go, it won't make any difference. Large brackish water fish like scats, monos, and puffers will be pumping out so much nitrate and phosphate that the 10 or 20 mg/l in the tap water supply will be neither here nor there. In tanks with smaller, low-salinity species, like gobies or orange chromides, you'd do much better using salt-tolerant plants (of which there are many) and using those to stop algae. Plants are far and away the best method for combating algae.

If you happen to have a surfeit of pure water, then try keeping a soft water aquarium. Very challenging, but worthwhile.

Cheers,

Neale

 

[Synirr]

Our tap water is actually softer than average for tap and has a pH of 6.8 or so. We've always had a good water supply, I don't even have to use dechlor for my tanks and don't unless it is a very large water change (70%+.) The only fish in the tank is going to be the waspfish mentioned here. Still, you're right, I don't think it would make that much of a difference.

 

[nmonks]

For waspfish, which are pretty tolerant of water chemistry, there's no reason to be fussed either way. By the time you've raised the SG to 1.010, the water hardness will be adequately hard and the pH should be around 8.

Algae in a high salinity brackish tank is just one of those things. You may as well accept that the rocks will get covered in algae, and decorate accordingly, so the algae blends in with the decor rather than messes it up. In other words, opt for something that looks marine-y to begin with, such as a small sea shells, craggy rocks, sand, etc. What tends to look dirty when the algae sets in are arrangements of bleached coral and big sea shells (like conchs and giant clams).

Cheers,

Neale

 

[Synirr]

I got some nice petrified wood for the tank today, that stuff is great at not showing algae... probably because it always looks dirty to begin with

 

[Synirr]

I could, but I'd have to wrap it all the way around the tank to really do much good, lol. There's a window directly behind where it's going to go, and a window pretty close on another side of the room as well. Afternoon sun shines through both of them and will hit the side of the tank primarily, but also the back and part of the front, kinda caddy-cornered. I know because it'll be right beside my 5 gallon DP tank, which has this problem . It's not really a terribly bad issue though, because like I said, the blinds are always drawn.... and light through one of those windows gets filtered through my 80 gallon first
Yes, that's right, the tank blocks the entire window.