View Full Version : live sand problem
I have a brown algae problem..can't seem to get rid of it..the tank is a 100 gallon with a sump[macro algae in sump] and using a 6 stage R/O unit for water..It has been running for over a year and still have the brown algae....Now if I stir up the sand on the bottom it is black underneath and it smells...Would this be part of my algae problem? Maybe to much nutrients coming out of the sand..also how do I correct my sand problem?[it shouldn't stink should it?].What is the best thing to help stir up the sand?[sand sifters? snail? suggestions?
Reefscape
10-22-2008, 10:10 AM
All the black your seeing in the sandbed is what should stay locked away within the bed, and stiring it up is not going to help. Yes, it does stink....
What flow do you have in the tank ( ammount ) and have you tested your source water for nitrates and phosphates? It could be dinoflagettes your suffering from...
tamz273
10-22-2008, 10:46 AM
I'm suffering the exact same problem... I was thinking of buying a Blenny or a Gobby to kinda go through the sand and keep lifting it... No idea how to get rid of it though...! ive got about 800GPH going throuhg the sump...
Amphiprion
10-22-2008, 11:32 AM
How long have you had all of your RO/DI filters (including the membrane and DI resin)? When was the last time you changed them or tested the product water's total dissolved solids, phosphate, and nitrate concentrations (after the RO and then after the DI)? This is important--we need to know things at the basic level, then move upward to figure out what else could be the issue.
tamz273
10-22-2008, 11:45 AM
well I get all my water from the LFS.. Alk = 1.025, Big 3's 0, Calcium 400... hardness usually 10...
any ideas?
Amphiprion
10-22-2008, 12:03 PM
Have you verified the TDS yourself? I doubt phosphate is very low, especially if you are getting an algae problem.
xsdbs
10-22-2008, 12:20 PM
[quote=Reefscape;1670681]All the black your seeing in the sandbed is what should stay locked away within the bed, and stiring it up is not going to help. Yes, it does stink....
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this black stuff you say is supposed to stay locked into the sand bed, I have seen this before in my tank and got worried ( yes, mostly because of the smell) and I used my python to suck up some of it. this was a while back before I was told by people here not to disturb the sandbed. my question is what do you do about this black stuff? I really don't see it much anymore but once in awhile I will see some light black ( gray ) in some areas and always wonder what is wrong. params are good== amonia 0, nitrates 0, nitrites 0, ph 8.2 - 8.4, salinty usually 1.024, temp 74 - 78. how often should an ro filter be changed? do you go by actual time or estimated gallons used thru the filter? how long would it take for this black to become dangerous to your tank? sorry about all the ( dumb ) questions and thanks in advance for your time and help
Amphiprion
10-22-2008, 1:10 PM
All the black your seeing in the sandbed is what should stay locked away within the bed, and stiring it up is not going to help. Yes, it does stink....
.................................................. ..................................................
this black stuff you say is supposed to stay locked into the sand bed, I have seen this before in my tank and got worried ( yes, mostly because of the smell) and I used my python to suck up some of it. this was a while back before I was told by people here not to disturb the sandbed. my question is what do you do about this black stuff? I really don't see it much anymore but once in awhile I will see some light black ( gray ) in some areas and always wonder what is wrong. params are good== amonia 0, nitrates 0, nitrites 0, ph 8.2 - 8.4, salinty usually 1.024, temp 74 - 78. how often should an ro filter be changed? do you go by actual time or estimated gallons used thru the filter? how long would it take for this black to become dangerous to your tank? sorry about all the ( dumb ) questions and thanks in advance for your time and help
The black stuff is iron sulfide and is an insoluble form of hydrogen sulfide under normal situations. It basically means there was H2S formation in the sand, but the toxicity was curbed by the presence of iron in the water. It doesn't really become dangerous unless it somehow becomes more soluble, such as sudden disturbance, etc. Theoretically, however, if left undisturbed, that H2S is, for the most part, bound for a long, long time.
RO membranes should be replaced as TDS meters dictate. You should find the normal rejection rate (usually a minimum of 98%) and make sure that the exiting TDS is comparable to, if not more than 98%. I personally wouldn't allow the exiting TDS to be higher than ~2-5 ppm, since each ppm increase in TDS effectively halves the resin life, making resin replacements expensive. If you can drive it lower, such as with a good restriction on the waste line (i.e. making sure you have a true 4:1 ratio of waste:product water) and the pressure is adequately high (60 PSI), then you should be able to get a good rejection out of it. This, however, will vary greatly, depending upon your source water. My source water here runs between 40-60. I usually have 0 ppm TDS out of the membrane to begin with, then the resins further extract any stray ions. So far, my membrane is already well over two years old and the resins are the same.
Prefilters, on the other hand, should be changed every six months or sooner if the pressure drops (via a pressure guage). You should also pay attention to how much water your carbon cartridges can process--if you manage to exceed the recommended processing amount in less than six months, you need to replace them more often. All of this will also extend membrane life.
yes thanks for the info on the Ro I will check this out