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anaerobic substrate?

4839 Views 15 Replies 4 Participants Last post by  Monster Fish
So I've got 72 gallon bowfront tank that I recently set up. I've got about 1" of the miracle grow organic potting soil capped with pool filter sand and some gravel. Maybe 1.5" of sand on top of the dirt and some gravel on top of that only in certain sections of the tank.

This has been set up and planted for about 7 days now. I'm seeing a lot of my plants rot/die/melt and am concerned it is due to anaerobic substrate. I've been making sure to poke around in the substrate daily (well sometimes every other day) and I am getting a lot of large bubbles emerging from the substrate when I poke around. I assume this is anaerobic gas which is bad for the setup. I also assume it is good that I am releasing it out of the substrate?

How long should I expect this condition to last and what else can I do to prevent/help the buildup of the gas?

I'm reluctant to do much to any of the plants (as far as moving and/or trying to trim any dead leaves/stems) yet as I fear I may just be overreacting and havent given everything enough time yet. How long before a newly transplanted plant should look "healthy"?
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I don't think the substrate is the problem. What is the light? What are the plants? Are you adding ferts?
I've got a 48" Finnex planted+. Only ferts are flourish and flourish excel.
I honestly do not know all the plants exactly. There are a few swords which seem to be doing okay. Some hygro kompact completed melted to the point where I cant even tell that it was ever there. I had some val and italian val that essentially went flacid and all just slumped over and/or melted away. Some ludwigia seems to be doing okay; but not great. Some hairgrass and a few others (some of which I have identified but have to check at home; others I honestly have not yet identified and the LFS was unable to specifically identify for me).

Here are a few photos that dont necessarily show the problems well but do show some of the plants.

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I think at this point it is just easiest to concentrate on what will grow. Vals tend to melt and they don't adjust easily to excel. I am not a big excel fan but I suppose that is just me. I think you should be dosing more ferts n p and K etc.
I'll have to look into some ferts. What exactly are you basing that recommendation on? Was there something in particular you saw in one of the pictures?

Back to my original question though, how else can I deal with the anaerobic gas from the substrate and how long should I expect to keep poking the substrate?
It is pretty normal that a substrate bubbles a bit. Depending on how you pretreated it, it could simply be air. It is much more likely that the plants are simply transitioning to the new parameters. Providing them with plenty of ferts will make that easier for the plants.
Makes sense. I treated the dirt by soaking, skimming off anything that floated, soaking again, skimming off the floaters; then I laid it out on a tarp to dry it out. Soaked it again, skimmed off the floaters and then I got pre-occupied by life so it sat soaking in a 5 gallon bucket for about 2 weeks (maybe longer now that I think about it). When I was ready to set up the tank that bucket o'dirt STUNK like hell! So I laid it out on a tarp to dry it again and then wet it before putting into the tank as it sits now.

I figured I may just be experiencing a transitional phase with the plants. How long should I expect that to continue?
Sounds like some of the plants have already adjusted.
So I'm still concerned that I have an anaerobic condition going on. I am poking the substrate daily and am getting what appears to be a lot of bubbles coming up. I can get a faint 'rotten egg' odor from it but its not overwhelming. I'm concerned it is basically killing almost all of my plants. I got a few MTS recently and am waiting on some more to arrive in the mail by the weeks end.

The only thing that seems to be surviving is a large amazon sword, some Ludwigia and some cardamine (or at least I think thats what it is). I am also getting decent results with some anubias which is on driftwood so therefore not being affected by the substrate. Crinum calimistratum is still alive; but each of the 'leaves' have been reduced by more than half of their original length.

Jungle val has completely melted away on me (two different plantings of it). Some crypts are doing ok but certainly arent thriving. There are some stem plants which have all but disappeared for the most part. Some stem plants seemed to be doing ok with some minimal damage/melting to the lower leaves. Then in the next day or two the whole stem just rots/melts away to nothing. I've got a melon sword (?) and a flame sword(?) which are basically melting away to nothing also.

The tank has been planted and filled for 2 weeks now. Am I just overreacting and need to give it some more time? How long should I expect to wait before I see some signs of growth?
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To be honest, our tank, just about every plant in there pretty much melted for the first 2-3 weeks. I think most were grown emersed and only recently introduced to the aquarium tanks we bought them from. Now they are starting to sprout new, green leaves like mad. I'm only running one T8 and a T5, gravel with Seachem Root Tabs, and dosing liquid fertilizers (Seachem's line), and one of those disposable cartridge CO2 kits. They did look absolutely HORRIFIC, but now everyone's growing like mad. We have Wysteria, Willow Moss, Java Moss, an Anubias (no idea the type), DHG, what I believe to be rotala and a ball with a plant attached that I don't know the name of. After they all settled in, they are all growing like mad. The Moss and the ball are growing very very fast, same with the Wysteria and the rotala.

It could just be them adjusting, ours were looking horrific. We thought they were all doing horrible until I had to pull out the Wysteria to trim the dead parts off, and realized it had very, very long roots, and brought up a bunch of gravel with it too.

I'd just give it some time:)
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When I say some plants are melting, I mean if you tried to grab the stem to pull the plant you would basically have a handful of goo that would basically drip through your fingers!

I hope I'm just not giving it enough time yet and will start to see some improvement soon.
Check the bag of soil you used. Some of the organic mixes use either chicken poop or cow manure. I haven't had problems with the former but the cow manure might be releasing too much ammonia for your plants. Check your ammonia, nitrites, and nitrates and be prepared to do more water changes. You also need some more plant mass so try to get some floating plants and some fast growing stems. As the soil matures, you can start adding more rooted plants.
I used the miracle grow organic choice potting mix. No cow manure listed. Just the standard "poultry litter" or whatever it might actually be termed now. One thing I did notice was the bag was pretty much full of twigs and sticks. I debated sifting it but decided that if I did, I would end up discarding more than 90% of what was originally included in the bag.

I've been testing daily and find 0 ammonia, 0 nitrite and 5-10 nitrate. Its a new setup, but I'm using seeded media out of my other tanks (and out of one tank that I completely broke down to set this one up). Doing daily water changes of at least 25%.

Anything in particular I might want to try as far as floating plants and/or fast growing stems?
The twigs and sticks should have been sifted since they take a long time to break down

Floaters such as frogbit and water lettuce work. Cabomba, anacharis, and hygros work for fast growing stems.

Another thing I noticed with your tank is that there is a lot of hardscape in your tank. With dirted tanks, I tend to avoid covering large areas of the substrate with wood or rocks. The reason for this is to give the plants more space to spread and root throughout the substrate and to help keep it from going anaerobic. Plant roots help keep the substrate oxygenated. If you can, try removing some of the rocks and driftwood and plant some more rooted plants in their place. Cryptocorynes do great in dirt.
The twigs and sticks seemed to be the majority of what was in the bag(s)! I'm really regretting leaving all that in there; but I guess its too late to change that now.

I went out last night and got some hornwort, wysteria, and something else (name escapes me right now) and have all that floating at the moment.

I'm reluctant to get more cabomba as that and bacopa is what seems to have melted the fastest on me so far! I think I'm going to let things simmer for a bit and then try a few more stem plants maybe in a week or so depending on what I'm seeing in the tank.

I have been removing some of the hard scape since those photos were taken. The driftwood is still there along with a few rocks. I've changed how the driftwood is in the tank. I now have one end resting on a rock so the majority of the wood is not actually on the substrate but hovers just above it (creates sort of a bridge/underpass). I removed the two pieces of flat slate that were lying on the ground and left in some of the other rocks with a "smaller footprint".

Crypts are some of the most recently added plants to my tank. I've got a crypt wendtii and another longer leafed crypt (maybe crypt balansae?). The wendtii seems to be doing ok. The balansae still looks green and healthy; but the few leaves are not very long anymore. Maybe I'll grab some more crypts in the next few days.
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Keeping those stems floating should be good. Wisteria turns into a weed once it's established.

The leaves on the crypts will melt but the plant will be fine. Crypts tend to go through a transitional phase where they lose most of their leaves when first transplanted. They should put out new leaves once they are established.
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