I started a 75 gallon tank in August. It has one mud turtle and for the last few weeks 7 tetras. In the last month or so the top of the white sand is turning light green. I am wondering what it is and what I might want to do to get rid of it. I can not suck it up.The test strips say less than .5 ammonia and no nitrates or nitrites and I still have to top up the tank with fresh water. I also added Nitra-Zorb to my filter a few weeks ago.

I am also wondering what I should do to clean debris off the top of the sand (Super Naturals sand). I have a small siphon hose with a bulb but that doesn't seem to be picking up anything.

yep you got algae growing on the sand.

snails will help

killing the lights and stopping feeding will kill off the algae.

Live plants will consume the nutrients the algae is currently consuming.


my .02

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden

Thanks. Though my turtle has been the perfect host to her new fish friends sails are her favorite food so that's not an option. How long can the fish go without food? How long should I turn the lights off for (have basking and uv).

fish depending on conditions can actually go months with no added food.

But for more normal conditions and with safety 2 weeks or so.

Usuallly my tanks with clear up and algae die off in a week but sometimes I have had to do a blackout for a month or more. But the latter is really rare.

Usually you will notice improvement in a day or two and be totally cleaned up after just a few days.

Again after that remember to adjust the light duration and feeding so that plants thrive but algae does not return.


my .02

__________________
fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden