Why cap Aquasoil other than aesthetic reasons?

 

To allow a layer of inert soil on top to remain once the aquasoil has degraded over time? Sorry if this sounds stupid still learning about high tech aquascapes.

 

Aquasoils will eventually turn to mush. This is in the 2+ year range but will almost certainly vary depending on the brand used. To my knowledge no one has done a longitudinal study on the life of these soils (ie which one lasts longest?). Anyway you can certainly cap aquasoil its done all the time. In my opinion this is aesthetically makes the scape look better but that's just my opinion. Most people will change their scape so much that 2 years is a long time to leave everything exactly the same. Additionally be aware that your layers will mix to a degree as you pull plants and replant new plants etc you will find bits of aquasoil coming to the surface.

All this being said, be aware that if you want a scape to last longer then say 6 or 8 months you will need to be dosing fertilizers no matter what substrate you use. What you dose and when will in some ways be changed by your substrate though mostly by your plants and livestock.

This being a high tech scape you should research different fertilizer plans. EI (estimative index) is quite popular. For an easy all in one liquid solution Thrive is a good way to go.

If this is a small tank then using an aquasoil is a decent solution. If this is a large tank then you may want to look into inert substrates and substrates with high CEC values (such as safe-t-sorb) because cost can be prohibitive if you are putting down an average of 2 to 4 inches across a 120 gallon tank. /shrug Just something to think about.

Good luck, and let us know what you decide!

 

Just my opinion here. If you're going to have unplanted open areas in the tank there's no need to put AS in those spots if you're going to cap it. It's just a pricey waste of a fine product. In areas that are heavily planted you're not going to see the substrate so why cap it. For sparsely planted areas cap it if you don't like the appearance.

As mentioned above, if you do cap it then it will eventually mix with the cap to some extent. Yes, it does become mud at some point and if you think you'll be moving plants around a lot then it's going to happen more quickly. I have four year old AS in my tank and it turned into mud long ago, but I don't disturb it much. It's completely covered in Marsilea and Lilaeopsis with a few crypts here and there.

I've done inert substrates with carpeting plants as well and I would not do another planted tank without AS unless it was an epiphyte only tank. The growth is quicker and fuller, IME, than an inert substrate.

 

On the flip side, I've got some tanks that have been running with Aqua Soil Amazonia since 2012 and they still look solid. Still buffering some, too.

In the past decade, I've only had one substrate turn to mush and that's Fluval Stratum - after about 5 years. I have other Stratum tanks that still look nice, though. Every other clay/dirt-based substrate I've used has held up pretty well. Azoo Plant Grower Bed, Mr. Aqua, Up Aqua, SL, Controsoil (doesn't hold up as well as the rest), several others.

I wouldn't buy something fancy like Aqua Soil and cover it with sand. Kinda defeats the purpose of buying something that looks nice as-is and can prevent flow that that kind of substrate really needs to work its magic. It's small enough (comes in different grain sizes, too) that it looks as nice as sand in most tanks.

If you're careful with your substrate, don't rinse it (that breaks it down), add water super-slowly (slower than you're thinking) and are gentle when planting and replanting? It'll last you several years. If you have the tank running for 5-6 years and it all turns to mush? You can easily cap it with sand then and use fertilizer root tabs. But at that point I'm betting you'd start the tank over or build an entirely new setup if you still love the hobby.

Some things to remember:

The only "stupid" thing in this hobby is not asking questions when you have them. Even if you think they're simple questions or things you've forgotten from long ago. Confused about something you can't figure out? Post on the forum. Need more in-depth reading on an issue, a YouTube video to help explain something, or just generally need to see examples of other people doing what you're trying to do? Chime in and get people to help. Everything is wild and new these days.

Read through tons of tank journals and scroll through all their photos. I find that to be not only a good way to get inspiration for aquascapes but to see how other people use various new products and plants, how they house livestock, what they do that works for them. Some journals go really deep and walk you through trial and error scenarios, failures, victories, all that. Really helpful even for experienced aquarists. I learn something new every day.

Don't buy something if you don't absolutely love it. Wait until you find the thing you love and get that. Even if it means you have to save up for a while to get it. The hobby today isn't like it was a decade ago when fancy tech was rare and expensive, tanks were all the same, all kinds of livestock is now bred in captivity, it's easier to keep rarer species. Back then I'd get something that merely got the job done. Now? I get things that are attractive, affordable, functional, exactly what I want. Makes everything way more enjoyable.