Read and researched still getting mixed opinions.

[atrox]

So here is the dilemma set up a 40 breeder 3 months ago and everything water chemistry and livestock wise is optimal. However when I started this tank my LFS had a large 700 gallon display that had been set up for a few years and developed a leak. As a result he pulled all of the livestock out and was selling the sand at 100 lbs for 25 bucks. First area where I realized I made a mistake is I did not rinse the sand as I thought whatever is in there will help with cycle which it did. I went through a hard cycle that lasted a few weeks. Parameters soon after leveled out and all readings were zero. Fast forward. Recently I have been dealing with cyano and algae and I can't but think a majority of this is coming from the sand. Flow is good, and I feed sparingly. Question is can I safely gravel vac without the 3.5 inch sand bed without disrupting to much?

[farkwar]

Don't most experts attribute Old Tank Syndrome to the sand, and what accumulates in it over a few years?

 

I would vacuum it all out gently, and toss it. And buy new sand.

 

If you want to keep what you got, vacuum it all out gently, then wash in hydrogen peroxide and/or diluted vinegar. Then rinse and soak it in salt water, use water change water if you want to "seed" it to live sand. Imagine all the diseases, bad bacteria, protists that cause PM in clams, parasite spores, protazoas like Cryptocaryon irritans cysts, etc locked up in that sand. Was copper or malachite green ever used on the 700 gallon tank?

 

 

 

Then again, cyano and algae can be just part of your cycle.

[frankdontsurf]

You bought a lot of sand that was sitting in a 700 gallon setup for years.. You basically bought used toilet paper. That LFS is ran by a dick. He should have sold you new sand and given you a small cup of his sand to seed if you wanted. Think of it like this, imagine what would happen if he mixed up all of his sand bed? You basically isolated this mess in your tank.

 

It will settle in time, the balance of bacteria needs time to align itself. I'd do 50% water changes every 7-10 days and make sure to be really gentle. If you do plan to vac it don't go all the way down, an inch at max.

 

I opted for bare bottom, I actually just pulled a 3" sandbed from my tank. Took everyone out, brought the water down to the sand level, dumped, rinsed the tank with sea water, put the rocks in, filled up with the water I pulled out, topped off with fresh sea water, and dumped all the critters back in.

[Subsea]

Of course you will get mixed opinions, why is that a surprise. There is good information in both #2 and #3 post. The wisdom is to apply it to your present situation.

IMO, the owner of LFS is a dickhead for giving you all the accumulated nutrients. I personally run high nutrient systems with many filter feeders and clams and would have no problem with a simple wash the gravel with fresh water hoses. With that being said, what do you do now?

At 3.5" you are somewhat shallow for a DSB.. While I do maintain DSB, I do not recommend them. Your sand bed depth is in between deep and shallow. This is a problem. First, what is the grain size? What livestock do you have and why so deep?

After 45 years of reef keeping, I have found coarse shallow aroggonnite substrate to be a powerful nitrification tool that and when combined with fast growing macro for nitrate and phosphate export completes my methodology of maintaining reef tanks.

 

Of course, you can safely gravel vac the sand at the top. If you have sufficient detrivores in your somewhat DSB, then you would not have to gravel vac. You did not give out enough information about your tank and your goals for your tank to get one concise answer.

Patrick

[atrox]

 

 

[atrox]

My goals for this tank focus on a nutrient rich water quality. I do not like chasing the elusive "pristine" tank and never minded the occasional algae here and there. I do not plan on keeping any SPS and want the main focus to be on euphillia corals and the like. This tank has been running for six months and and as far as corals go all have thrived. Against my better judgement I did not rinse the sand as I always cycle fish less and figured the decay in the sand was a good way to start this particular tank. I just did a wc and gravel vac'ed a small portion of the sand with no ill effects.