Suggestions on substrate
I have a planted tank with 3 goldfish. It's been established for about 2 yrs but I have just recently started dabbling with aquatic plants. My substrate is sand currently. My knuckle head fish keep kicking the sand around looking for food and what not and uprooting my plants (they are big guys, the little one is 7"). So yesterday, I cleaned the tank, both canister filters, trimmed the plants and put them in hydroponic pots. I also laid down some river rock, not a layer but a good amount. For the most part, the plants are being protected by the pots but the fish keep knocking debri around (it's hard to completely clean sand without sucking up the sand itself). I want a clear tank dang it!! So my question is, if I layered my sand with substrate..will it keep my big guys from digging through my sand? Maybe something more coarse. I'm open to suggestion because this is frustrating. My concern though is whatever substrate I lay down (Flourite or something of the like) on top of my sand. it will eventually become mixed and not separated in layers over time. I have even contemplated just getting new fish when these guys pass someday, but I really love fancy goldfish..they just get huge in my 75 gal. Looking forward to advice or suggestions. Thanks!