Removing a discusting old sandbed!

[1979fishgeek]

i been battling raised nitrate and phosphates last few months, my bio pellets were inaffective after over two years of working well. I switched to NOPOX and I cant get my nitrate below 8-10ppm and phosphates under 0.5ppm. I did some poking about in my sandbed which is few years old and it’s pretty disgusting infact it’s filthy! I siphoned out 6sq inches today and it was pulling out sooooo much detritus that the water looked like chocolate milkshake.....that be where the nitrates are coming from I think!

So what’s the safest way to protect my corals while I perform the detritus sandbed exorcism?

PLAN: I’m going to siphone out sections at a time straight into a water butt as I do water changes 150litres at a time in a 1200l system. But I wondering if I should add something as the organics being released is considerable and I’m upsetting a very old substrate layer. But what be best? Something that could detoxify ammonia and/or a product designed to boost the bacteria and consume sludge nitrates and phosphates boost the nitrogen cycle? Any product suggestions please?

I’m not planning on adding any sand back going bare bottom, but any advice on what to expect and damage control is greatly needed!

Thanks

 

[sfin52]

I would continue with that plan. Dr Tim’s make some great products like waste away and refresh. If you are real careful you won’t release all that much into the water column. You could also add a diatom filter when removing sandbed

 

[User1]

Various posts I've read here and elsewhere seems that most just syphon it away with each water change. Nothing dramatic or all at once, just a bit here and there until it is all gone. I don't have much advise because I've personally not done that before and I usually run with 4 - 6" deep beds in my tanks. But there are some posts here whereas people have done what you are trying to do. If you haven't maybe try a search and see what else pops up. In any case best of luck.

 

[D_dot]

I just sucked out all my sand from my 14 biocube because of high nitrates. After one week the algae problem I’ve been fighting is going away.

 

[jimmyzhou]

Or .. try. When u do the water change. Use phyton system. Get the sand out with water together. Do it for few time. Maybe will be more safe?

 

[TinyChocobo]

How deep is your sand and are you planning on replacing it?

 

[Saltlife]

I have a question for you. Sounds like it would work in my head. Could you use a wet dry vac, hold your hand over the end stick it in the sand and turn it on. Sure it will suck up some water but if your in the sand should suck up more sand than water. Just a thought.

 

[jimmyzhou]

But the wet dry vac can take out more water than sand. Python system a lot reef clean there sand bed with Also do water change at that time. Didn’t mean take out all the sand at 1 st. U can part them as 4-6 time water change

 

[1979fishgeek]

Or .. try. When u do the water change. Use phyton system. Get the sand out with water together. Do it for few time. Maybe will be more safe?

That’s what I’m doing. I ended up filling a entire 150litre water butt only taking out 6sq inches of substrate. It’s gong to be long a process with only 1,800 inches left! Lol But rather do it that way than take all the rock and coral out!

 

[1979fishgeek]

How deep is your sand and are you planning on replacing it?

It varies from 2 inches to 1 mm that’s from flow. The problem areas are over .5 inch thick. Goes to show if I did just a few millimetres it would have been fine or if I done a proper deep sand bed as they tend to take care of themselves. I’m not replacing it afterwards I’m going to put encrusting Montipora in its place.

 

[1979fishgeek]

I have a question for you. Sounds like it would work in my head. Could you use a wet dry vac, hold your hand over the end stick it in the sand and turn it on. Sure it will suck up some water but if your in the sand should suck up more sand than water. Just a thought.

I’m using a syphon so it takes the water out anyway. It clogs with bits of broken coral/rock or tube worm casings every few seconds and I have unclog it but it still way better than alternative. Plus can do water change change at the same time.

 

[maroun.c]

you can either go very slow removing a bit of sand with each water change (IF this durty wouldn't recommend removing more than 5-10 percent in one go. Take out a small portion completely out each time dont uncover half of the thicknessa nd leave it to realease nasties it accumulated (read about Hydrogen Sulphide)
Another safer option is to keep doing water changes, add GFO and carbon dose (biopellet or other ) Also use organic binding additives (many vendors make them and they are quite efficient) this will clean up things (will take a long time ) without risking releasign things that can kill your tank.

 

[TinyChocobo]

I’ve read that deep sand beds have a limited lifespan even if it’s 10 years. It seems like cleaning out a DSB would be even more work and trouble than removing a shallow one.

 

[maroun.c]

That's why many shifted to Remote deep sand beds (RDSB) as they were easier to take out or restart.

 

[TinyChocobo]

That's why many shifted to Remote deep sand beds (RDSB) as they were easier to take out or restart.

So a shallow bed in display and a deep in the sump? I’m not really wanting the bed for bacteria just for appearance. I figure I can put a block or two of marinepure in my sump if I want more bio area?

 

[jimmyzhou]

What I did is. Tank has 1-1 1/2 inch sand just for look refugium has 7-9 inch sand bed. With algae. And in the sump refugium for miracle mud. That was on plan now wait for zen reef build my mud tray in 2 weeks. I can done my mud

 

[1979fishgeek]

you can either go very slow removing a bit of sand with each water change (IF this durty wouldn't recommend removing more than 5-10 percent in one go. Take out a small portion completely out each time dont uncover half of the thicknessa nd leave it to realease nasties it accumulated (read about Hydrogen Sulphide)
Another safer option is to keep doing water changes, add GFO and carbon dose (biopellet or other ) Also use organic binding additives (many vendors make them and they are quite efficient) this will clean up things (will take a long time ) without risking releasign things that can kill your tank.

I’ve been doing the carbon dosing for over two years, Bio Pellets worked great at first almost too well. But then they were not getting no3 below 25-30ppm and tried different manufacturers, doubled the quantity, changed reactors but to no avail. So I switched at Christmas to NoPox. That took a while to show any significant reduction, then it suddenly dropped to 8-10ppm I’m dosing at max dosage of 3ml per 100l on a auto doser which doses every hour during the night and every other hour during the day. I’m actually really reluctant to remove the sand, it’s scare the detritus out of me! lol But I just feel it’s going to be a increasing pollutant as time goes on, totally my fault for not setting it correctly at first and then thinking the microfauna would do the work for me. Hoped if I act now before the start off ‘old tank syndrome’ effect. Would love if I could find a product that could remove the fine mulm in the bed though, be amazing if I did! It was a real eye opener just how much brown sludge/silt is trapped in it.

 

[1979fishgeek]

That's why many shifted to Remote deep sand beds (RDSB) as they were easier to take out or restart.

Learn something new everyday (especially in this hobby!) never heard of a RDSB but I am consulting Sir Google straight away

Remember when Plenums were the rage?! Lol actually I laugh, but I had one that worked ok..ish!

 

[DeniseAndy]

I have removed a lot of sand from my 210g. I did it over many water changes because it was going on 7 years old and nasty too. No issues. Go slow and you should be fine. Just takes time and lots of water changes.

 

[1979fishgeek]

I have removed a lot of sand from my 210g. I did it over many water changes because it was going on 7 years old and nasty too. No issues. Go slow and you should be fine. Just takes time and lots of water changes.

Thank you, crazy how much this is worrying me. Just keep thinking of all the things that can go wrong with disturbing old sandbed. I’m going to pull put just 6 square inches at a time during waterchanges, even if it takes me a year.